windshield vid cam mounts

Window Mount

The "Groofwin" is one of the better ones I've seen. There are other out there as well. I making the assumption you're talking about a passenger or driver side window here. Just do an internet search on "Groofwin" and you'll come up with it.

Kirk Photo also has a window mount but we're talking $$$ here.

There are cheaper ones, just go to E-Bay Photo and search for "window" and you'll come up with plenty.