I would recommend...
Benson Auto Body
15032 Jackson St
Midway City, CA 92655
I had my rear bumper repainted and it looks ALMOST like factory. Paint is a little thick but it looks great! Their turn around time is not great but their prices are reasonable.
10886 Westminster Ave
Garden Grove, CA 92843
Don't be fooled by is little hut. This dude can copy any key you bring him and he'll do it for cheap. Best locksmith in town. I've been going to this guy for years.
520 E Jamie Ave
La Habra, CA 90631
Disc Brake Rotors & Pads | R1Concepts.com
They don't do any installs but they sell great brake products. Picked up drilled and slotted rotors from them and the quality of the rotors are great for the price.
Rene's New and Used Tires
8249 Bolsa Ave
Midway City, CA 92655
Best prices on tires hands down. They do a very thorough job and most problems they'll fix without any hassle.
Audio, Alarm, Navigation and basically anything electronics.
Ask for Johnny (714)276-7394
This is kind of ghetto but I've been going to this dude for years. He use to work at a shop but now he just does mobile work. Most of the time he will come to you if you're in the OC area. You got to speak a little Vietnamese to understand this guy. ALMOST anything electronics this guy will take on. If it's something new you got to bare with him but I've never seen him give up on the job. His prices are unbeatable.
Most of these places you can tell them Anthony sent you. I've gone to some more than others but for the most part they know who I am.
I would NOT recommend...
8555 Katella Ave
Stanton, CA 90680
COMPLETE rip off they'll try to cheat you at any cost. The Vietnamese guys there will scam the crap out of you (keep in mind I am Viet). The Mexican guys will give you a straight and honest answer. I had my rims mounted and balanced here and they told me that my tire is really bad and that it will shake on the freeway no matter what I do. One of the Mexican guys there came up to me and told me just to install the hub centric ring and the problem will go away. I told the Vietnamese guy to do that and he straight out told me "it's not gonna work it will still shake like crazy" I told him it's fine I'd rather spend 20 dollars then spend 500 on tires. After everything was said and done I immediately took the car on the freeway and guess what no vibration! I love my Vietnamese brethren but the guy that works there is a complete jackass.
Purrrfect Auto Service
7421 Westminster Blvd
Westminster, CA 92683
This Purrfect auto gives all the rest of them a horrible name. The guys there are complete assholes. I went there about a year ago and I have never been back since. They slammed my hood down about 10 times extremely hard. I mean after the first 2-3 times you don't figure in that idiotic head of yours "hey maybe I should stop doing this shit and see what the problem is?" NOPE he kept slamming the hood. I know what you're thinking "why would you let this guy slam your hood so many times?" I was sitting in the waiting room and I kept hearing this bang over and over. I looked around and saw that there were no other customers and I was like OH SHIT! That's my car. I ran outside and see this guy just repeatedly slamming my hood down. I stopped him and closed the hood myself. I brought the manager out and told him that if there's anything wrong with the radiator or anything near the hood I'll be seeing you again. The manager was as stupid as the mechanic. The manager told me "It's not our fault the radiator has nothing to do with the hood being slammed". A couple days later smoke started coming out of my car. Guess what the plastic on top of my radiator was cracked. I was furious but I didn't want to deal with those assholes so I just had the radiator replaced.