Comment by tachyonbeam

There are some good resources available:

http://www.softsynth.com/links/programming.php

http://sonicbloom.net/en/63-in-depth-synthesis-tutorials-by-...

http://www.acoustics.salford.ac.uk/acoustics_info/sound_synt...

It's actually fairly easy to program a virtual analog synth.

There are also packages like Sonic Pi and supercollider which are designed to enable music live coding.