Here are a some of my favorite vanity number resources and phone links. But this will give you a good start.
Humans do it better.
Telecom Information Resources One of the most exhaustive Telecom sites ever, with over 7500 links. This list is being expanded and updated all the time. Use the search and if it's out there, you'll find it. This index lists a number of information sources in the field of Communcations and Telecommunications. I use this for a variety of things when tracking down regional numbers.