Hi,
There is an interesting site that I recently came across called AudioTuts+
It provides a place to upload sound design tutorial to. Here is one done by Mo Valans.
If anyone is interested in doing more advanced sound design tutorials for AudioTuts+, just let me know.
http://audio.tutsplus.com/tutorials/sound-design/how-to-create-classic-fx-synthesizer-patches/
Gavin.