Antimoon This site improves learning motivation, modern learning techniques, and more. The site developers believe that "English classes and grammar exercises are not the best way to learn English" and their goal is to "...explain English to people, especially the important things which are often ignored by teachers (such as pronunciation)."

Studying phonetics on the net with Phonetics Resources. Site has categories on phones and phonemes, waveform analysis, speech synthesizers, and much more. 

The Okanagan College site is another good source for pronunciation.

Peter Ladefoged's Vowels and Consonants is here and features an introduction to sounds and languages.