Also, the main areas depend on what you are into. Rembrantplein has a lot of big regular clubs (the kind of ones you'd find in any European city) and is mainly aimed at tourists. Leidseplein is more of mix of touristy Amsterdam meets resident Amsterdam. Paradiso is a great club and is located in an old church. Melkweg, The Sugar Factory and De Kroen are all also in Leidsepleine and are quite good. You should check what's going on before you choose though as there is no specific music type for each club and it changes with the night.
There are many other places such as squat house clubs and pubs and pretty much anything else you can think of really, but these are scattered all across the city and so you're best bet is probably to consult nl20 or Amsterdam Weekly (if it decides to make it's return to publication)