[Users] application via voip?

Hi all - Not really sure where to post this question as I am just starting to research this issue. We'd like an all VOIP solution where we have a telephone number that terminates at our server. At our server, we'd like to: 1. get their phone number via caller ID. look up data with the caller id. 2. generate a wave file based on the data returned & play it to the user over the established voip link. How is this done? Totally new to the game here. I've read about DID origination, SIP channels, SIP peers... its all quite confusing! I'm a java developer, so something that works via Java would be great, but scripting in various languages is no big deal. The application doesn't need to do much more than query a database & choose a WAV file to play back based on that info. Thank you-- Matt Pease ParkingHero, Inc.