Easy enough. The joysticks, buttons and trackball can all be procured from
www.happcontrols.com.
Happ Supers are probably the best "overall" 8-way sticks, but people have said that the Happ Competitions are better for "fighter"-type games. There's a good review comparing the Super to the Competition
here. You could also check out some of the joysticks from
Ultimarc.com too. Quite a few people have used the E-Stick from Ultimarc as their 4-way stick and have liked it.
While you're at ultimarc.com, there's your interface answer. Get an I-Pac to interface the joystick and buttons and an Opti-Pac for the trackball and spinner. They both have USB options on them.
For the spinner, go for the
most excellent OSCAR Pro from
www.oscarcontrols.com. Or, if a push-pull spinner for Discs of Tron is more up your alley, oscarcontrols.com will have those available shortly.
That help?