What part of Germany were ya plannin' on seeing??
We have a few suggestions of what you could see in southern Germany near Austria. If you're into scenic places, Neuschwanstein is a beautiful castle near Munich. It's a little bit of a drive, but some of the nicer castles around there. If you want to see thousands of American's, go to Munich. Although Oktoberfest is a lot of fun, but I'm not sure when you're going. It's real touristy. The Bodensee is really nice and there is plenty of nice scenery in that area as well.. borders with Austria. Also, the Black Forest is really nice to visit. You will see a lot of stereotypical Germany in that region.
As far as Czech Republic, we've been there... Prague in particular. That's a pretty city, but I found it a little dirty. It's real interesting to see how the other half lived in the communist block.
We live in the northwestern part of Germany.. about 8 hours by autobahn from that area that you'll be. Most of the information we could give you is up here and it's not really touristy up here. Not sure what you're interested in, but if you give me some info, we might be able to help.
Drop me a PM... if you need to.