Ronni,
First a good map is a start, but you can go to USGS and download your areas topographical map for free in PDF. Save them via computer and then you could go to any copier and print them. Not sure how your office frowns on reproducing maps, but they would be black and white, or if you take them to Kinkos, etc. See my post about Maps. Will give you some ideas.
As for San Diego, my good friend family lives in San Diego, we served together in the military. His very large Filipino family are not preppers nor he. I did remark that possibly quickest route would be toward Imperial Valley, but your facing some serious desert terrain that must be negotiated and that requires some serious planning to include water and fuel. If your footing it, then I'd make sure I attend a few desert survival courses that would prepare for you to coexist and survive.
Heading up the 5 or 15 are going to be not sound routes, even taking the 8 would be dangerous, but I'd opt taking the 8 until I got to the California 79 and go up through Cuyamaca, at least you would have water and then head into the national reserve. At least the route well north is near Twenty-nine Palms, Marine Corps training base, your going to bump into units if crap hits the fan. I'd just make sure before you leave, were not in martial law, use the shortwave radio with handcrank/solar power to keep informed.
Since I only lived in Central Part of California in early 90's that the best I can offer. Its been a long time since I visited San Diego (early 90's right after first Gulf War).
As far as hotels forget it, when Katrina hit, hotels were sold out all the way to Dallas, Texas. If your talking California, think about your population density. Also, I'd shy away from people in general, I'm sure some will tag on to that...definitely avoid camp grounds, people get very desperate when they fear the unknown. You are marked because your going to be in complete control because you've been prepping! Your better staying out of sight. JimLE and I were discussing rail trucks as a Exfil vehicle since he and I agree that days after an event or SHTF that railroads will stop completely. Like the airlines did when 9-11 hit. We just were discussing options, I'd make sure I would have some good railroad routes marked out on map, check the forum, can't remember who posted, but he had a link to a pretty uptodate website that had all railroads in U.S. similar to MapQuest or Google, but railroads.
I'd try to work out with some other prep people who are on this site and group together. You will see most, of us believe grouping is a viable option of staying alive.