Big Brother knows where you live

This is driving me bonkers. The banner ads from AdultFriendFinder.com say "MEET THESE GIRLS FROM YOUR AREA!" and show some camwhore-ish pics.

They list the cities these women are in, and it really is from right around where I live. I checked out the banner ads from a few different websites (not ones I use often or have an account with) and I see the same thing.

How can they tell where I am? I use a big ISP where there is nothing region-specific about my IP (for example it's not some small ISP that only operates in a few places or something like '*.roadrunner.net' which operates out of the US South/Midwest zone; at least it used to)

If there is some geographical-specific data that's associated with me being on the internet, how can I found out what it is, and disable it?

I'm fucking tired of going to so much effort to stay anonymous on the internet. It's a constant struggle. :-(

>>1
Lol. You can't be anon at the intarweb. You request stuff and expect it to be delivered to your computer for browsing, right? You HAVE to use your IP, where the fuck do you want replies to go? IP blocks are usually assigned to specific nodes within ISPs. And they let these IP databases know, or the guys running these databases found them. Now anyone who owns a server you connect to may tell you're from city X. zOMG!!! Your privacy is at danger!! Seal your windows!! Warrior of freedom, help me!! Stupid privacy.