Perk, I'm in Riverside and have dealt directly with Toyota of Riverside, Toyota of Corona and Toyota of Temecula. I will never do any business with Toyota of Riverside. They are worthless IMO and seem more intent on selling you a new truck. Toyota of Corona is good but also a bit slow or busy (long wait to get an appt and then long time to get repairs done). I've had the best luck with the Temecula dealership and they even gave me 10% off my parts and labor when I mentioned the TLCA, etc.
It really depends on what you need done too. If it's engine diagnostics then most cruiser heads in the area are not equipped to deal with it. But if its suspension, drivetrain stuff you could try the guy in San Jacinto (I think its Rock Solid Off-Road /(909)654-5404). I'm drawing a blank on his name right now. You can also PM Big_Moose (joe) as he is on the board on and off and does a lot with FJ55-100 (evan) who is a cert. lexus mech).
Yotamasters is a Toyota speciality shop in Corona, dont know much about them but they are into the Toyota truck customizing. yotamasters.com
no expernce with them, Allpro is a great shop too