Well, I'm back here in the states. Yup, I did haul my old POS 10 lb laptop, the Kryptonite New York Fuggedabout it chain, and the Kryptonite New York U-Lock. And I never once used them! OMG, my bike was so heavy, I couldn't even lift it over a small fence.
1,4. I used the Garmin GPSMap60CS which came with the North America City Select Maps. You can d/l large sections of the map to the GPS which even includes details of local businesses. I had all of my maps loaded into my GPS and still had lots of memory available.
2,3. I bought the Adventure Cycling Pacific Coast maps and used them. On their web site, you can d/l full GPS waypoints for those maps. I then auto-plotted a route between all of the waypoints and pretty much followed that down the coast. There are some places where there are separate bike paths (i.e. instead of riding on the I-5) and that is not exactly mapped on the GPS (since it's for motor vehicles), but it was close enough. It really saved me a few times from getting lost after making a wrong turn.
5. I use 2 AA batteries at a time. Only used 4 total for the trip.
I don't know how you older people used to get around with a GPS. Other than my bike and camelpak, that was my most important piece of equipment.