Our E-Z TILES sets allow you to customize the tiles before you print, giving you thousands of variations. We offer dungeons, wilderness areas, caverns and more. I don't know if this is what you had in mind but it may be worth your time checking out:
I'm finding Terragen very interesting, but I've honestly only begun to play around with it. It looks like it will create just about any kind of terrain you can imagine.
Also try googling AutoRealm, it does decent continent maps and is free.
Even better is campaign cartographer from what I hear and I have seen folks do nice things with it as well. I understand it might be a bit challenging to learn though.
Oh, wow! It's been years since I've looked at that page. I think it even looks the same as it did years ago. Boy, does that bring back memories!
If my guess is right, the OP is looking from something that will generate terrain in say at most a 200 ft. square? I can't think of anything that would randomly generate something like that, not terrain-wise at least. One suggestion would be to look at various map products or adventures and steal setups from those.