For stock racing -
You are going to get a million opinions here, so here are mine. Most decisions are going to be a) budget based or b) track support based. See what others run and what is sold at your track, this will make support easier.

Motors 17.5 - Reedy, SchuurSpeed, Fantom - same if mod, just mod wind. (for beginner stick with stock)
ESC - Hobbywing Justock for stock racing or v3.1 if for stock and mod later
Battery - Reedy, Orion, SMC or Trinity 4000 mah+ shorty.
Charger - Orion touch or ICharger duo if for stock and want to charge higher amperage (will also need power supply)
Radio - Airtronics or Futaba - model depends on budget. Also some are happy with Spektrum higher end models.