over at audiofanzine they have a series of 24 articles (regularly expanding) in which they explain all kinds of synthesis and other things related to sound generation like effects. There is also a lot of soundexamples that help you really well understand what all those parameters do..

sound-synthesis-explained-part-1

For those that never dared to dive under the hood of the sounds of their arrangers, it might be a great place to start. For all others, its a great read, with good examples, and its never to late to learn something.