Welcome aboard!
1. Are they messy? Yes and no, You do need to clean their cage and litter boxes everyday or every other day. The cage is usually the messiest thing. We let our bun roam free in the house and it is surprisingly clean.
2. are they easy to leash and litter train? Some buns can get used to the leash but not all bunnies like them. Yes you can litter train them! My bun was VERY easy to train,but others may have trouble. It just depends on the bun.
3. What do they eat and how much? A good hay based pellet, lots of Timothy hay, Salad greens like Romain lettuce, carrot tops, cilantro, and many, many more. Check out rabbit.org (HRS - House Rabbit Society)for a good list of rabbit veggies and treats.
4. I saw some bunnies at a pet store, and they were soo cute, and they were so scaared of me! if i got one of those, would they be easy to get used to human contact and be easy to pick up? Yes the bunny would get used to you. If it is a young bunny and you handle it often it may even like being held and petted, but just to warn you not all bunnies like to be held and some prefer to be left alone. Like humans each bunny has it's own distinct personality. If you're "really" interested in getting a bunny you could also check out your local animal shelter.
5. Rate a bunny on a scale of 1-10. 10 being best pet ever! 10, 10, 10!!!!!! I've had other pets and having a bunny is the best pet, they are my fav.