A) A good SF bookshop or bookshops in the SF/LA/vegas areas, and

I haven't been to a bookstore in ages, as I have such a huge pile of books to go through already, but...
Since you're going to be in Berkely anyway, you may want to stop in at The Other Change of Hobbit.
Santa Monica has something that's probably overkill for you -- Barry R. Levin
Science Fiction & Fantasy Literature. Not an SF bookstore, but still possibly of interest to you is OpAmp, which has the biggest collection of technical books you could wander through. Of course, if you're just looking for your generic Star Trek/Wars-like SF pulp, you can get that stuff pretty easily at any Barnes & Noble (who can sometimes have other pretty reasonable titles, as well).