Springs, rear camber kit and if you have the money replace the dampners at the same time. If not, you can run on the stock dampners but they will wear out very quickly and you will be pulling it all apart to replace them, saves time and money to do them all at once.
Oh and yes, this should be in the wheels, tires, brakes and suspension section.
Oops, forgot part two of your question. Camber kit I believe is around $30. As far as springs there are several to choose from, for example, Eibach makes the Sportline lowering springs, 2"-2.2" drop for about $195. If you have the cash and choose to replace the dampners at the same time plan on spending @$300 depending on what brand and where you buy them.
As far as install, from what I've heard not difficult if you have the right space and tools but time consuming.
No they are two different things. The camber kit allows you to adjust camber positive or negative to allow for the drop in the suspension. With a 1.5" drop you usually don't need a camber kit and any adjustments can be made with what you have stock, it's when you drop further that you need the extra adjustment capabilities. It's actually just a set of two bolts.
Dampners is another name for shocks and struts, a totally different item. But yes, if you drop 2" you will definitely need the camber kit and at some point new shocks and struts.
they typically say anything over 2" is going to require a camber correction kit. you can get the kit from mcnews (www.mcnewsautomotive.com) for about $30, and take that kit in with you when you get your car aligned, so they can do it all at once, save you some money.
any drop over 1.5" will pretty much require you to replace your stock dampers (shocks/struts) within a year. anything LESS than 1.5", you will be fine for a bit longer, but it's still recommended to replace your stocks with aftermarket.
if you have any questions, anything at all, just shoot me a PM, and i'll help you out the best i can, and point you in the right direction.