Also get a 200gb or more hardrive for other storage. Intel p4 extreme editions are also good. You can also overclock them.
Some good pc u can buy if you don't want to buy are: Falcon Northwest Mach V (a bit expensive about 7000 something), Polywell Poly 939N-FX55
As for monitors, depends on preference, if you want a good LCD spend more then 600, but a less expensive one should do. w/ crt anywhere from 100 bucks and above.