Do you have to get it through your phone provider or can you get it independently from a seperate company? How much does it usually cost?
You could get it through your phone company, or you could probably buy one at Radio Shack or WalMart. It might be $5 a month. But, it is so worth the money.
Call your local phone company. Mine (SBC) charges about $4 per month per line for number-only ID; add $2 for both name & number.
You need two things: subscription to the service (thru the phone co) and the display device to see the numbers and name.
You will probably have to provide the caller ID display box (no more than $30), although this is built in to many phones nowadays.
And a lot of the time, the telco will run a deal - order caller ID now, and get a free (very basic, which is all you need) Caller ID display! I think Caller ID through my telco costs 5 bucks a month on its own, but I get it as part of an all-inclusive package that costs be about 20 bucks a month (for features I don’t even use, I keep meaning to cancel all but the caller ID).
Just a comment…I’ve used CID in a big city like Los Angeles and a small town. In the big city, so many people block their CID that it is nearly useless. In a small town, at least the ones I am familiar with, where most people not only don’t have CID but don’t even know it exists, almost nobody blocks their signal, so you can see who is calling you. Then it becomes useful.
Other notes: there are codes that you can use to block the display of your outgoing CID on a call-by-call basis if you want. These codes are not universal, so check with your local phone company. You can also have your line blocked always, and then use another code to un-block on a call-by-call basis.
Also remember that you cannot block your CID from appearing on incoming 800 numbers, on the theory that if they are paying for the call, they are entitled to know who it is.
Hmm. That’s not my experience in Kansas City. Nevertheless, I don’t answer calls where the ID is blocked. The overwhelming majority are telemarketers. If an individual feels compelled to block (and frankly I don’t see why people do this), he’ll just have to address the answering machine.
Why would someone with a legitimate reason for calling not want you to know it’s them? I can see why telemarketers and such would block their numbers, or a private individual who’s harassing or stalking someone, sure. Then you would totally not want someone to know it’s you. But a private individual who has a legitimate reason for calling? Why wouldn’t you want your friends and family or the gas company to know it’s you calling? That just doesn’t make much sense. Seems like it would be much simpler just to get an unlisted number.
I think the driving force is generally not letting people have you rnumber - not to keep them from knowing that it’s you calling. There are all kinds of reasons why a person might not want some people to have their phone number; if the reasons are plentiful enough, it gets easier just to block your number at the outset instead of blocking it on a per call basis.
Incidentally, when I had an unlisted number with SBC (and this may have since changed) it automatically made it so that my number was blocked.
I always wondered what would happen if you put a new Caller ID-equipped phone on a non-ID line.
Absolutely nothing - the display just stares at you blankly.
Amendment: I had a phone that displayed “No Data” when calls came in.
If you don’t want that many people to have your number, why not just get an unlisted one and be done with it? I mean, anyone who really wants your number can flip through the phonebook and get it, otherwise. Blocking caller id doesn’t seem like a whole lot of protection.
I get mine for free with my cell phone.
I’m not sure why you’re assuming people don’t do that.
Because your posts imply (to me, at least) that most people in urban areas use permanent caller id block to keep people from getting their number, rather than just getting an unlisted number. You know, when you said everybody blocks their caller id, so it’s useless. I just kind of figured if you meant folks generally had unlisted numbers so they didn’t pop up on caller id as though they were blocked, that you’d have said that. It’s just us talking past each other, I guess. Sorry about the confusion.
No problem, but I’ll just clarify to be sure 
(Incidentally, I’m not the poster who made the implication that people in urban areas use a block more frequently.)
When I had an unlisted number, it automatically blocked my number. That may be the case in general, but I don’t know if it is or not. If, in some areas, an unlisted number is not automatically blocked, it makes sense to then take the added precaution of blocking your number. I fully agree that it doesn’t make much sense to have a blocked number, but not have an unlisted number - it sort of defeats the purpose.
California is different. When caller ID first came out, there was a great hue & cry that it invaded the privacy of the caller. The issue was framed almost entirely in terms of evil businesses using caller ID to let them harvest numbers for telemarketing purposes whereas before caller ID your calls were safely anonymous.
As a result, the initial rules provided that the default setting for transmitting caller ID was off, and consumers had to opt-in to have their data sent. Almost nobody did, since the only people who had caller ID receiving equipment were businesses.
After a few years when the novelty wore off, the industry lobbyists got the rules changed and as of about 1998 they’re like most of the rest of the country: by default caller ID transmission is turned on unless the subsriber requests for it to be off. http://www.ora.ca.gov/consumer/alerts/telecom/cons_callidprivacy.htm
And slowly but surely more and more people have caller ID reception since most new phones come equipped for it. But any Californian who hasn’t re-jiggered their phone service in 10 years probably has callerID transmission switched off, making them appear as Private or Blocked or some such to anyone with caller ID reception.