First as I see your on the good step, You ordered beadlocks.
The rim is your personal choice I think. For me I just ordered some DWT Reinforced Front 10x5 rims, I'll put some 20" Maxxis Razr 2. For the rear, I went with 8x8 DWT Beadlocks, and on them I'll put some 18" Maxxis Razr 2. The Razr 2 are one of a grippin tire. I use them in snow at this time of year and they really grip. You could go with some 9x9 rims, but for the tires I think the standard is 18". 20" are too big for Mx or Oval racing like I do. JMO