servers

Go to this link: http://73rdregiment.com/servers

Find the one you want and then go into black ops and open the console by pressing "~". If nothing comes up, make sure it is enabled in your multiplayer options. When you have it open type this: /connect <ip> (ex. /connect 173.199.94.15:3094).
When you are in the server, hit esc and click add to favorites and you should be able to find it later in your favorites tab on the server browser.