I'd reccomend "Electronic Projects for Musicians" by Craig Anderton. It's an excellent book that shows you how to make everything from a simple preamp to an envellope follower. Back in the early '90s, I built a couple of projects. It was a lot of fun, but I should warn you: it's not the cheapest hobby. All those components and tools can really add up!
Anyway, if I ever got back into it, as a joke, I'd love to construct: THE ATTENUATOR. I'd give it a super hot paint job, make it look like the baddest little device on the planet. Components? 1 box, one pot, one switch, 2 jacks.
BTW, I love your little icon. That little

thing always got on my nerves.