Hi hoodie,
1, here's a picture! (two different types).
2, it depends on how many free slots you have on your motherboard. If you only have two slots, then you will need 2x 1gb.
3, you'll need to know more about your system, as there are lots and lots of different types of
RAM you can buy, and only a few that your system will actually support. It's probably best to take your current
RAM in, and ask for the same type!