Prices are coming down fast, so time is on your side. Being in a hurry to buy will cause you to pay a higher price, both because you may look desperate, and because the asking price is falling. Seriously consider renting for year or two while you get to know the area. Then decide where you want to live, then buy.
As for buying with minimal agent help, I would figure that buying from out of state is exactly the case case where you DO want an agent. That way, you can see the most appropriate houses (out of tens of thousands in the county) during your visit to San Diego. My wife and I are planning to do this when we visit potential cities… we also get to “test drive” the agents by seeing if they can refer us to suitable properties)
Also, presenting offers directly to the seller (and bypassing their agent) won’t help if the seller already has a contract with a broker.