Agreed.
I have 2 and leave them alone alot more than 9 hours a day. My crutch / saiving grace is this:
One of the coolest doggy doors ever invented.
It affords me the luxury of being irresponsible. I never have to rush home or feel guilty if I leave the dogs alone for an extra-extended period of time. Whenever they get the urge, they jump outside into their fenced in yard, answer mother nature’s call, chase a few squirrels and head back in.
Count me as another single dog owner who says “go for it” with the caveat that you pick a suitable breed of dog.
Although adopting a dog from the pound is a comendable activity, you should think carefully about it–in your case, behavioural qualities are going to be very important, and those can be harder to predict with mixed-breed dogs. I recommend getting a good book on choosing a breed. I recommend Tortora’s The Right Dog For You, which worked well pairing me to my dog.
I raised from a puppy, although I had the luxury of telecommuting for the first couple of weeks and going home for lunches for several months after that. Once she matured a bit (emphasis on a bit–still very puppy’ish!) she had no problem with 9 hour days: I picked a breed that does well alone and is inactive indoors (although plenty active outdoors–we run together). I did have to write off the apartments carpet, though. 
If you can’t raise a puppy, then you can still get a purebred adult dog. Most breed organizations have a rescue society of some sort; also, sometimes breeders have an animal they’ve finished and don’t want to breed. You might want to look into a rescue greyhound. They come mature, trained, do well alone, are easy to care for, and are very affectionate, especially for sighthounds (my dog is a sighthound as well, though not a greyhound).
One thing about doggie doors, though–in some places, dog-napping is popular. People steal dogs to use them as bait in dog fights. If your area is safe, then they are I am sure a wonderful tool for your dog to get some exercise and relieve its bladder. But if you are in the big city (I don’t know from Salisbury) and don’t want unimaginable things to happen to your dog, then you may not be able to use a doggie door. We would never consider one for jeevpup but maybe if we were in the 'burbs it would be a safer option.
It is probably best to find out what your neighbors with dogs do. (We have learned many useful tips from folks at our dog park.) They can also recommend good obedience classes (which help the dog but mostly you), boarders and vets and might even be willing to walk him for you.
Oh, and ours is a mixed breed rescue dog and one of the most well-adjusted dogs we know. (No comment from Eva Luna, please!) My sister has pure bred dogs she raised from puppies and they are nut jobs. So consider all your options when choosing your new best friend; there are drawbacks and benefits with each type.
Here I am, not commenting. 
BTW, everyone give a big, warm SDMB cherry-popping welcome to jeevwoman, formerly known as *jeevgurl! (I knew she’d never end up as Mrs. jeevmon, but that’s a whole other story. I also knew she’d get sucked in here eventually, but that, too, is a whole other story.)
I do it. I got my puppy at the beginning of August - I was careful about selecting him based on a) getting along with my bunny and b) being able to tolerate being alone during the day.
He’s pan trained so I don’t have to worry about him needing to go - he just heads to the pan when he gets the urge.
He’s got about 1,000,000 toys.
I leave the radio on for him.
I give him cookies when I’m leaving.
Really, he’s fine. I get home and he’s excited, but it only lasts about a minute then he’s back to himself.
However, I have no children or husband taking away time from him, so when I’m home, he gets ALL my attention - this could be a mitigating factor.
I think if you select your dog type carefully, and are prepared to give him/her lots of loves when your home you should be ok.
By the way, astro, as a single man, you are no doubt aware that a cute, friendly dog is the one of the best wingmen you can have. The only thing possibly better is someone else’s baby. So if you can make it work financially and timing-wise, go for it.
(Insert usual disclaimers re: gender stereotyping.)
I’ve got a German Shepherd who does just fine – got her as a pup only 10 weeks old. I built a dog run along my garage with a dog door for her to come inside. She’s got her food and water inside along with a dog house for her to sleep in. I live in WI and this has provided plenty of shelter for her. She seems to enjoy being outside where she can watch the squirrels, birds and kids play in the park. Of course she needs to either walk or play when I get home everyday and she’s totally an inside dog when I’m home.
If you’re concerned about the dog needing more during the day, a dog walker or doggie daycare are great choices. The doggie daycare near me charges $15/day, so it depends on your location.
As for travelling, Mia (my doggie) has a lot of fun at the kennel. I found one where they let the dogs out to play together 3-4 times a day for as long as the weather permits. She’s always exhausted when she comes home from the kennel and they rave about her because she plays well with any dog. In fact they use Mia to be a playmate for the dogs that don’t want to play with any of the others.
Go for whatever you’re willing to do. Keep in mind that pups are tough because they need to be trained. Mia and I took a couple weekly obedience classes plus daily training/playing for a couple hours at least. We’re going to start changing her daily walks to jogging now that she’s old enough – I waited for her to be at least 1.5 years old so her joints were well formed.
I can certainly second the greyhound idea. We’ve had hounds - at times just one, other times two - for 10 years and have always left them at home during the day while we work. They do fine. They are, of course, excited when we get home, but I think it has as much to do with the fact that they know a walk and dinner will be shortly forthcoming as anything else. If I surprise them by taking a half day off work, they’ll come strolling out of the bedroom looking confused - after all, I’ve just interrupted (another) nap.
If you aren’t used to going straight home after work, that’s one adjustment you’ll have to make unless you can get a dog-walker to take pooch out mid-day or get a dog door. Even then, you should plan to spend as much time as possible with pooch, particularly if you plan on having just one. Dogs need and thrive on attention, and if you have even the slightest inkling that it might be more of a hassle than a pleasure to provide that, it might be a good idea to think of getting a different sort of pet instead. Dogs that get the attention - and the exercise - they need are much less likely to have behavior problems, and therefore are much more pleasant to have around in general.
One thing about rescue groups, though - they can be unresponsive and unhelpful. We are currently looking for a sibling for jeevpup, and would like a lab or lab mix. Unlike jeevwoman’s sister, our plan would be to adopt a dog from rescue or from a shelter, rather than buying a puppy from the first pet store on the side of the road. We contacted one Lab rescue group, whose website says that they serve “northern Illinois and southern Wisconsin.” They also have an area code widely used in the northern suburbs of Chicago. We were curtly told that they could not adopt to us because they had no volunteer who could come to Chicago to check us out. Now, I appreciate that they are staffed by volunteers, etc., but if their definition of “Northern Illinois” excludes the largest single city in Illinois, which just happens to be in the north part of the state, they might want to be more specific. They could, for example, say that they “serve the following counties in Northern Illinois and Southern Wisconsin” and provide a list that excludes Cook County.
We put our name into another Lab rescue group a few months ago, and have heard diddly-squat.
It’s frustrating as hell, because we’re trying to do the right thing in how we adopt a second dog, but these organizations aren’t being particularly helpful. I know that they’re tightly staffed, but it is frustrating to be a willing and able adopter and still be turned away because they don’t have time to deal with you.
I work a similar schedule (and then some) have a 5-month-old golden retriever puppy and we’re getting on just fine.
I’ve had to make a couple of sacrifices, though.
I get up an extra hour early to take him out and play with him before I need to start getting ready for work.
I also come home on lunch to let him out of his kennel.
He gets a walk every day, rain or shine.
I used to kennel him up at night and during the day, but now he’s old enough that his bladder will last it through the night and he’s only in his kennel while I’m gone. He sleeps most of the day, and he has food, water, plenty of chews, and lots toys in the cage to keep him occupied.