What kind of experience do you have? Any machine experience, what condition are the cars you'll be working on etc so we can suggest a good first order? There are probably some things you dont need.
To keep your entry costs down I'd go with the following
Meguiars Gold Class soap (available locally)
2 5 gallon buckets (home depot buckets are nice)
2 grit guards from AG
2 microfiber wash mits from AG (one wheels one paint)
Cobra Guzzler - Either the real big one, or 2 of the "supremes" if you're doing trucks of any kind. One supreme is good for regular cars.
Porter Cable Dual XP if you want to start on machine
Meguiars Ultimate Compound
Meguiars 205, Pinnacle Finishing Polish. Or others if you like.
Klasse AIO
Klasse SG (if you'd like), or Poorboys EX-P is super easy to use as well.
From there you can pick any number of waxes if you'd like. Lately i've been using Pinnacle Liquid Souveran and/or Poorboys Nattys Blue Liquid because they're easy by machine.
If you're into paste wax, I'm a fan of regular old Mothers Pure Carnuba, which is cool because the dish it comes in is big enough for a 6 inch pad.
For the PC I like to use 5.5 inch CCS pads.
Yellow if you think you'll need it - Compounding heavy correction
2 oranges - All purpose polishing, Megs Ultimate Compound works good with it
1 or 2 whites - Another good all purpose, finishing polish, Klasse AIO pad
Green - Klasse AIO
Blue - Waxes etc
red - Sealers
Those are the pad combo's i've been using, but you'll definitely have to experiment on your own and take input from the experts on here. But thats pretty close to what my first "real" order was.