basicallyy i would say the other things you will need are:

active monitors (ideally) - 300
small mackie mixer - 400
8 output soundcard - 300
midi keyboard - 80
filter unit - 100
aphex 109 eq - 100
cables - 50

sampling, seqeuncing & synthesis can all be done in cubase/logic....

but everyone has a diferent approach....this is just what i would do with that budget....