Just bought a 2009 with package 3 . Very nice car but it is going to take some getting used to. Probably the first vehicle I'm actually going to have to read the drivers manual to figure out all of the features and different settings. If your in the market of one, it's a great time to buy.
Yes, Read the Owner's Manual. Twice. During breaks in the reading go to John1701a's site John's Stuff - Toyota Prius and more >Prius Info>User Guide I which will help you make a lot more sense out of things quickly. Then read the rest of John's site. When you are ready to graduate from that, Google Hobbit's Techie Rants, and learn more than anyone is supposed to know about your Prius.
You got a great car and at a good price. Enjoy! Doc Willie's remarks are right on - the user guide on John1701a's site is a great tool for newbies like us.