PCB design guidelines

Does anyone know of any online resources or can even give some advice in this thread regarding trace widths, creepage distances, etc? All the resources I've found are for high frequency or digital circuits which are not relevant to me for audio circuits.

I want to know as I'm currently coming up with a combined soft start and soft switch circuit and want to know what sort of trace distances etc I should use to maintain safety.
 
Geez, thanks for the intelligent post mik!

I'll reiterate what I mentioned in my first post:

All the resources I've found are for high frequency or digital circuits which are not relevant to me for audio circuits

Now what I was asking is for people personal experiences, or any other direct links to information that is relevant to audio and in particular, amplifiers.