Alternative to join SWAT4 server due to problems described in the previous article is an application named Qtracker (thx to {SoE}Mirta for link). Download is available here.
After installation choose SWAT4 from the game list. Then click Servers->Find Internet Games (I have to do this after every start but maybe there is a setting to do that automatically). Servers are then loaded from the Qtracker master list which contains 41 servers currently. It remains a mystery to me, how can servers be added to this list. If you know, share it with us please as when I try going to Qtracker forum, it says my IP is banned for spamming.
You can connect to the server of your liking directly from the application. Though this tool is no longer in development with the last version released back in 2010, it is the best alternative to GameSpy I have seen so far.
Hint: if your server name is not displayed correctly, change or remove the color code before the string that was omitted.