i make server in this site....name bilal1980(username)so when i entered custom ip ....then suden error comes gametracker say:server not found.............plz tell me what i do ....my cs 1.6 ip is 192.168.15.33:27015

When you add the server, GT will come up with useful suggestions. You need to ensure that nothing is blocking GameTracker from being able to scan the server on that port. Routers, firewalls, etc can be in the way. You need to ensure that you either open ports, portforwarded, or whatever you want to do to ensure GT can reach it. GT IPs are available in the error message or in one of the sticky topics in this forum if you want to whitelist.