At times I pick names from the top of my head, but I love to read and lots of times I have picked a theme, of a sorts, from the series that I like and feel fit the town. Sunset Valley I pick names from N. Singh's Psy/Changlings, as it is based in Calif, San. F. I think.
C. Feehan's Carpathian's is best for Riverview, vampire series that is based in the Carpathian Mountains.
Moonlight Falls, it has such wilderness aspect that I decided to go with a Native American theme for a couple of games. I picked a N.A. name for a last name and then NA names that are nature oriented. I use the NA name for wolf, fox, deer, eagle, moon, and such. One family was named Tsalagi, (Cherokee) and the sims were Amitola (female means rainbow) and Dyami (male means eagle). The son was named Mako (earth).
I have also used the names of characters from another book series for Moonlight Falls, they are Breeds, humans with animal DNA, so have used the names of the characters. In one family the wife is Dawn (she has Cougar DNA) and Seth, her mate (all human) and son is Taber (lion DNA).