Anyone from SoCal? Calling all my Californian friends!

I'm going on a trip to San Diego and LA at the end of June and I need some advice on any and all of the following:

1. Where is a good place to stay in LA? Not too expensive but doesn't have to be cheapy-cheap either...

2. What are some "must see" things in LA? I've been there before but I was only 10 at the time and so remember nothing. Touristy things are cool, but anything that might be worth seeing that isn't a "hot spot" is helpful too!

3. I'm staying at the San Diego Marriott Hotel and Marina - on West Harbor Drive...and it looks great. What are some good places to eat in San Diego?

4. I've kind of planned a Veronica Mars Stalker Day for myself and I hope to visit a large number of the filming locations in and around town (Balboa Park, Mars Investigations, their apartment, Oceanside High, etc.) - is there anything else that I should avoid or that is a must see?

San Diego is actually our first stop and after 4 days there, we'll be driving up the coast to LA...probably via the Pacific Coast Highway...I can't wait!

Any suggestions or comments are welcome! I am really excited about going and I want to make the most of my time there :)