I was like you too, confused on which stethescope to get in the begining. I ended up with an Ultrascope. I really like it, it's so cute too, get lots of compliments on it too. Also a Littman is great too, I think that's the favorite among a lot of people. I think you should go to a local store and ask if you can "try" them, they let me do that, take someone with you and listen to them, see which one you like best. Also, remember, they can get expensive, so use that as your decision maker too. If you're scatter brained and leave things all over, I would suggest just getting a cheap one, you wouldn't want to lose a $100+ stethescope!
PS Just make sure you get one with soft ear tips, my first one was really cheap and had hard plastic ear tips, ugh, it killed my ears!!