If you read German, check out http://www.gulp.de. It will tell you about rates for freelancers.

In Germany, a DBA with 2 - 4 years experience can expect between 100k and 140k DM in the west as a permanent. An average salary is around 110-120K DM. Collecting this information is pretty difficult though.

In the east, take at least a 20% reduction.

Just FYI, the IT Greencard program requires that incoming foreigners make at least 63K DM in the east and 78k DM in the west of Germany.

1$ = 2.2 DM (roughly)

Good luck.