I'm a trail rider so not much help - but I do know that there is a track in Victorville (just off the 15) and the gorman track (Hungry Valley). I also think there is a track in San Diego, Cahuilla or El Cajon.
Ocotillo wells is in San Diego county (think Salton Sea area). We are actually headed out to Ocotillo on Friday for the weekend. Hope to put in quite a few miles on the trails out there. Your welcome to join. I'll post directions to where we will be if you want.