I just saw the new york sound synthesis course on youtube. It's pretty good, but I wonder if there are any guide or pdf with the most common used settings in music, like a string pad on trance music or getting a certain instrument sound.
Yes, there's the rightfully famous Synth Secrets series by Sound on Sound magazine: http://www.soundonsound.com/sos/allsynthsecrets.htm
And the classic Synthesizer Cookbook: http://www.amazon.com/Welshs-Synthesizer-Cookbook-Programming-Universal/dp/B000ERHA4S
It depends on you maths and computer programming level. Sound synthesis is very much related to sound analysis which requires Fourier transforms and many other mathematical backgrounds.
Once you studied discrete Fourier transform, filtering and computer programming, you understand how VST and programs like 'Live' or 'Reason' are made.