Hello dhackbert and welcome to MR.
Check out the forum '
which one should I buy' which also has a
comparison matrix in the wiki. That should give you a good idea.
To find more info specifically about the
Nook &
Kindle check out the relevant subforums. And don't be afraid to ask any questions - lots of helpful people around here
For a whole heaps of free ebooks, check out the
eBook library from MR. Sooooo many free books, lovingly formatted by MR members. That'll keep you reading for a while.