I didn't use them myself since I didn't find this site until I'd already applied
. From what I've read though, the study guides are a big help. Here's the link to the file library from where they can be downloaded:
http://www.airwarriors.com/forum/filelibrary.asp
I used the ARCO study guide, which had a lot of aviation questions and a pretty good section on spatial apperception and many practice problems. Unfortunately, for someone with no aviation background, it didn't go into detail on much. It's mostly to test the knowledge you already have.
For the aviation stuff, I went down to the local Barnes and Noble and picked up "How to Become a Pilot" in paperback for 15 or 20 bucks. It was exactly what I needed, short and sweet (maybe 200 pgs). I ended up with all 7s, which I guess is OK. Unfortunately I was too old for NFO, but I got Crypto at least.
I've got no advice for you on the nautical questions because I honestly don't even remember anything about it on the test. I didn't bother studying since I've been a squid for 12 years now. I should have some idea by now.
Good Luck,
Bill