I'm consistently amazed by the volume of web pages churned out by chess enthusiasts around the world. Here's a sample of the useful and amusing stuff from my Favourites folder. If you have any of your own, just shout.
Obviously all this stuff is outside of your webmaster's control, so we take no responsibility for anything going on in this section. But you knew that anyway.
There are two forms of online chess. In one, you play the game in real time, almost as though you were facing an opponent over the board. In the other, you play like a correspondence game: the games are played on the server, but you play in your own time. So, you make a move when you login, and your opponent replies when he logs in. The time limit is usually about a week maximum between moves, but most people make at least one move once a day.
One very good server for this kind of chess is letsplaychess.com, based in Barnet chess club, apparently. It's free to use, but for a tenner a year, the extras are well worth the money.
If you want to play correspondence in German, then try here.