When buying online, please be very shoosy on who you buy from. The only place I ahve used so far is Miami Tropical Bonsai. My tree was in great shape, and you can tell it was grown bonsai. many places will jut take a random bust, cut it down, stick it in a pot, and sell it. the other place to use (I have not used them YET... I will soon for my Japanese Maple) is evergreen garden works.
You haveto answer this question first: will the tree be kept inside?
If so, limit yourself to a ficus. Some say you can also grow a chinese elm indoors too, but I would reccomend the ficus as it is hardy... meaning hard to kill
When buying from miami tropical bonsai: it will ship ina plastic pot. It is fine to keep it in there... you'll want to pickup a tray to put underneath it. I bought the tray to a window planter from home depot. cost me a few bucks. Its only used for humidity, and to catch the water that will run out of the bonsai pot when you water it. The only other real thing you'll need right off the bat is a watering can (or oyu can be cheap like me, and make holes in the top of a bottle
) and maybe pruing shears. I just bought a $6 pair of fiskars at homedepot. That sould be all you'll really NEED. When it comes time to repot, youll need to research soil, but you have a book already, so you might already be in the know!