Your server is not showing in the in game server browser?
The servers are automatically in the master list, unfortunaly there are some problems on the in game server browser list which cause not even 1/10 of the servers to load for most people.
In your in game browser when refreshing the internet list it will display about loading 17 000~ servers, but in reality only a few hundreds or thousands will load.
This is a game bug with the in game browser, InfinitWard are aware of this problem and they said it should be fixed in the next version.
You can verify in the InfinityWard/Activision master list directly on the web to be sure it is indeed listed correctly on activision side.
Go to: http://stats.callofduty.com
Type in your server IP and click Submit.
If your server is listed and is written in black it means that the server is indeed listed on the master server.