Well it depends on just how deep you want to get. If this is just a casual interest, then Matt Ridley (who wrote the Red Queen), actually has quite a few more books with a human evolutionary theme.
All of Jared Diamonds books are worth reading.
Robert Wright's book on the evolution of morality is a good one.
Then of course there is Gould. He's pretentious as hell of course. But you made it through Dawkins, so you can suffer Gould. Wonderful Life, though not really on human evolution directly, is a classic.
Then you've got the real classics--old stuff by guys like Dobzhansky (his later speculative stuff--he has one book on human evolution, I forgot what it is called though) and Ernst Mayr can be good.
It might be worthwhile at some point to pick up a used evolution textbook, either Futuyma's or Ridley's. I also think it would be worthwhile, if you're really serious with this interest, to go back to the source, so to speak. A lot of evolutionary biologists cast something of a skeptical eye on evolutionary psychologists (only a fraction of whom I think are actually trained in evolutionary biology) because, a) they can't test a lot of their claims, or don't present them in a hypothesis driven manner, and b) they don't necessarily always use evolutionary theory appropriately.
That's a generalization no doubt, but I don't ever recall seeing an evolutionary psychology symposium at the annual Society for the Study of Evolution conference (which is the professional society to which nearly all evolutionary biologists belong). I mean I would love to see such talks if they had them (it beats the hell out of listening to talks on gene flow in plants or phylogenetics of north atlantic cod or somesuch). Which is to say there isn't a lot of communication between the two groups. Which is why I suggest doing some background reading in evolutionary biology before you dive back into the uncharted waters of evolutionary psychology.