I dug out a bunch of related threads from the last year or so. There is some overlap, because some of the more recent threads contain pointers to earlier posts, but all of it is good reading:

Need Advise from LoudSpeaker Experts

Building my own cabinet....

Resistance! Lets get my Ohms Straight!

Gettin a new amp

building cabinets

buy a cab or build one?

bass cabinet porting

Good luck. Post again if you need more info.
L.