well, it can support a maximum of 4Gb of memory, and has 2 memory slots meaning you could fit in 2x 2Gb sticks in there although they are pretty expensive.
Youll need to look for the following ram:
and more importantly it needs to be SO-DIMM
memory otherwise it will be too big!!!
Here are a few examples from Tiger Direct:
And a 2Gb stick from NewEgg
edit: regarding installing it, its not hard at all - if you do decide to do it yourself make sure you use the right screwdriver size
on the back panels, if you dont the heads of the screws will be damaged and you certanly wont be able to take them out without using screw extractors and replacing them. Installing the memory in the laptop involves flipping up the slot and then putting them in like you would with desktop memory. If you dont understand what ive just said you probably should look into it a lot more first