I prefer metal and I do not like bamboo. They're too slow for me.
It's a shame you don't like knitting with circs, because an interchangeable set is really the way to go for economical versatility. I never use straights anymore. (And my body thanks me :D)
You can always go out and buy needles in every size just so you have them, but the best way, IMHO, is just to get the needles as you need them. Hobby Lobby has the best selection and the best prices here in HSV.
Though I've had my gripes with them, one of the cheapest and best places to get yarn is online: Knitpicks
. The deals are phenomenal, and they have all sorts of yarn types for all your knitting needs. And Elann
is also apparently wonderful--I've not purchased from them yet, but other KH-ers have, and I trust their praises.
Of course nothing compares to visiting the LYS...touching the yarn is just wonderful!