I believe the biggest is 80GB actually.
1. Well. I have 919 songs on there, and not one of them has been bought. You do the math
2. I bought mine at Best Buy here in Canada.
3. Well. It ranges from 1GB to 80GB (I think) I know 60GB for sure. Theres 1, 2, 4, 8, 30, 60, and possibly 80 aswell.
4. Headphones, USB (Which is the charger aswell), Some white thing that I dont need, and some install booklets. I dont think it came with a CD
5. My 30gig Video was about $300 canadian.