Maine. The only two I haven’t been to are Maine and North Dakota, so this was an easy choice.
I have never been to the USA at all, so I guess I have a clean slate to work with. As an Australian , I feel attracted to the big sky, desert states, so I think I’d have to go with Arizona as a first choice. Honourable mention to Nevada and New Mexico. But you’d definitely find me hunkered down in some sleazy truck stop somewhere. I like that sort of thing.
New York. I’d love to visit NYC.
I second Maine… or anywhere in New England, really.
Right now I’m on a Seattle kick though. That rainy cloudy weather really appeals to me. Plus that Space Needle thing really freaks me out. I must get there! 
I’m almost at the point of road-trippin’ with LoganDear. I would have to go with the Pacific Northwest, though Oregon or Washington I don’t know.
The whole East Coast thing has gotten boring, the Midwest is, well, the Midwest (no offence intended), and I’ve done all of New England. I’m not into hot and humid weather, so forget about the South East.
Visited 38 states, but never been to New York or any of the New England states.
So either
[ol]
[li]Ground Zero, Little Italy and the Metorpolitan Art Museum[/li][li]American Revolution sites in Boston[/li][li]Vermont in the fall[/li][/ol]
Shagnasty, she is right across the way from Tulane at Loyola. Do her parents worry! 
North Carolina. I’ve even considered moving there even though I’ve never been. I should probably check it out first.
Vermont. I think it’s the idea of the woods, what I’ve been told the autumns are like. I’m not sure I’d enjoy the winters there (I read somewhere Vermont has 2 seasons – 9 months of winter and 3 months of bad sledding), but after putting up with 35 St. Louis summers (this summer not included, it’s been wonderful) I would like to try living somewhere cooler.
Well, there are only three states I have never visited or lived in: Mississippi, Florida and Hawai’i.
Guess which one wins?
I third Colorado (I’m pretty sure I’m only the third person to mention it!). 
Never been, but the idea of that state has appealed to me since – well, you’re going to laugh, but since Mork & Mindy. :o From what I’ve heard, from folks who have lived there, I’d be better suited to either the Boulder or Colorado Springs areas than Denver (don’t know about any other areas). My company has a Colorado Springs office, but unfortunately they don’t use their own tech writers out there (all of the writing services are centralized at headquarters, which is where I work). Maybe I can change our business practice one of these days. 
At the very least, I’m hoping to figure out a way to travel to that office on business at some point so I can check out the area in person!
Another vote for Montana, as it has always seemed like a cool place.
I could also do Wyoming.
Washington. The idea of mountains and rain is quite appealing.
Montana. I think it would be a lot of fun to spend some time on a working horse ranch. Not just a fancy dude ranch, but some place where I would really get to work on the ranch.
it would probably be ok if they had a spa…just a smallish one
That site is out of date. Montana reinstituted speed limits several years ago. In fact, there was only a window of a few years where it lacked them. BTW, the joke in Montana is that it is 9 months of winter and 3 months of tourists. (Certainly not true.)
I’ve been to all 48 of the lower US states. But not Alaska or Hawai’i–would be hard pressed to decide between which of those I’d rather see since I want to go to both. I’ve also been to every county in Montana, so I can’t even play this OP as “what county in MT that I haven’t been to would I most want to go to”.
I’ll just list a few of my most egregarious omissions of cities I haven’t been to yet: Miami, St. Petersburg, FL, Las Vegas, Los Angeles, and Tucson. hmm.
I’ve been to most of the eastern and southern states, so those are out.
California would definitely be my first choice. Lots of things I’d like to see there.
Other states I’d like to see would be Colorado, Minnesota, Oregon, and Washington.
[QUOTE=Shagnasty]
I had to go with Montana. It has gorgeous scenery, a low population, as well as Yellowstone and Glacier National Parks.QUOTE]
Uh, with all due respect to my neighbor’s to the North, whom I truly love, you do realize that the vast majority of Yellowstone is in Wyoming, don’t you?
For me, I’ve been to most of them, but I will say Maine.
Since Hawaii is excluded by the OP, I am going to guess Florida because does anyone really want to visit Mississippi?
Heh? That seems rather out of place with the others.
Hey, the city smells like piss, the country smells like shit. Whaddayagonnado?
I think the only states I’ve missed are North Dakota, Mississippi, and Alabama, so I’m gonna cheat and say New Hampshire (I’ve driven through the tail end, past Portsmouth on Route 95, en route from Massachusetts to Maine).
I love New England, and I’ve spent lots of time in Maine, Vermont, Connecticut, Massachusetts, and Rhode Island, but never any appreciable spell in N.H. I’d like to see the Presidential mountain range, do some hiking and climbing, spend the night on top of Mount Washington in a high-wind blizzard.
Idaho. 50 gazillion potatos and the pics I’ve seen can’t all be wrong.