Hi - I'm Simon and I'll probably be running race control when you come along for the first time so just remind me I spoke to you here
I'll answer your point in order:
Paints - No idea. I don't paint my own shells.
Tyres - You will want Schumacher minispikes for our outdoor track (and also most other astro tracks too). The normal compound is yellow, which is extremely grippy in the dry, but doesn't work well in the wet. However our astro is exceptionally high grip and I actually prefer the slightly harder green compound for 4wds as a result. This avoids the grip roll yellows get on dry days and has the advantage of working in the wet too.
None of these are good bashing tyres as they wear far too fast. However that wear rate means after a season or two of racing you'll have a lot of 'too worn to race with but still functional' tyres you can bash about with.
ESC - The Orion is very popular, as is the Hobbywing V3.1 which is the same thing.
Servo's - Savox is the main brand of high end servo's you'll see. They certainly aren't the only people who make good servos but they are the most common.
Cells - Good ones are quite expensive if you want proper BRCA approved ones. Or you could just get some
Turnigy Nanotechs from Hobbyking. These are a lot cheaper, and work just as well. Can't use them for regionals but fine for club meetings.