The following are excellent places to visit if you need help with speakers and audio, and I highly suggest you check them out.
Speakchat.net is home of the Speakchat java chatroom. (It's not actually IRC, if you're wondering.) While not the most popular of chatrooms, it's the hangout of a few extremely knowledgable individuals, including WmAx and AndyG. Just click the "chat" button in the upper left, and you're done!
The DIYaudio forums have been for years a major center of all DIY audio building and design. Wether you're into single-driver speakers or complex class-A solid-state amplifers, you'll find a variety of experts on it here. Also featured is a sub-forum dedicated to the excellent work of Nelson Pass, who himself posts there on a regular basis.
Audiokarma is the home of a lot of old-school audio enthusiasts. If you want information on your vintage Halfler amp or need to repair your Pioneer HPM-100's, this is the place to go. It's also a frugal audiophile's paradise - with a little work and combing of Goodwill stores, it's possible to get stereo equipment superior to that sold at Best Buy for a fraction of the price.
DIY Mobile Audio is the hangout of car-audio enthusiasts who do it the right way: using high-quality drivers and custom crossovers. If you want to get a serious sound system in your car without a massive drain on your wallet, this is the place to do it.
5.Parts Express "Tech Talk"
While less formal than the more complex bulletin-board system employed by the other listed forums, Tech Talk is a useful resource nonetheless. If you need a quick question answered - or just want to look at other people's designs - this is a great place to go. Also easily found is information on Parts Express' clearance drivers, and assorted very inexpensive speaker designs based around them.
Finally, feel free to E-mail me any questions you may have. I'm still learning as I go along, but I'll help to the best of my ability.