For ease of use I really like to recommend the Chemical Guys Black Light. It's a great product. Apply by hand with a blue pad or a wax pad. Do the whole car and by the time you're done applying it should be dry in the first places you applied it and you can then start buffing it off with a nice MF towel.
But yes, find out what type of buffer your friend wants to sell you. Dual action orbitals are very safe to get started with. They don't have enough power to damage your paint and if you press too hard the clutch stops the spinning action. Not only is it safe, but it lets you develop a feel for how hard to press down. They also generally don't leave holograms and if you have badly hologrammed paint a DA buffer is used to remove and clean them up.
For $125-150 you can pick up a brand new buffer. Either the Porter Cable XP7424 or the Griots Garage Random Orbital.
Check out the major detailing websites for reviews and write ups on both. You may want to consider a whole "kit" that includes some pads. I have found it better to just buy the buffer and the pads you need. Many of the kits come with 1 pad of several colors when you really need 3-4 pads in 2 colors only.
www.detailedimage.com
http://www.autogeek.net
Both of those are pretty reliable sites and they run sales all the time.
I am only a hobbyist detailer. However,
@ClearCutSi is a pro. Hopefully he can chime in too. I'm sure he has some good recommendations.
EDIT: Ok so VigLink isn't letting those links go to the right place. Type the addresses in.