books for a converting guitarist/pianist

[rorschah]

I checked out the FAQ links, but I'm wondering if there's some book out there that might be better for somebody like me.

I've got about 12 years of piano, about 2 years of guitar, and some jazz theory. Most of the beginner's basics books look like they spend too much time teaching me stuff I already know. I'm looking for something that tells me about... well, basic physical technique for the bass, and then how to think bass, grooves.

I just want to be a solid rhythm bassist here - for stuff like soul, reggae, dub.

I was looking at the Friedlander grooves book, which looks pretty cool, except I don't have the dough for a drum machine right now. Blew it on a new bass.

Thanks!

-thi