callback system

I need a experienced VOIP programmer to create a callback system. We are starting from the ground up so this may be a long term project. in a nutshell: User will call a number (voip number) registered with asterisk (or whatever). Get the CID, search the database if it is a authorised caller. Hang up the line. Call the number back. Prompt the User to enter the number he/she want to call. Get asterisk to call the number, blind connect them. Release it. You will also need to advise me and help me find the best solutions for this project. (hardware needed, DID provider, bandwith needs, etc.)