Build aTube Amp - Do It Yourself Tutorial
I came across this tube amp tutorial. I like the absolute thoroughness of the tutorial, Everything is covered from soup to nuts. The schematic is customized, which may be a good or a bad thing. It uses relatively low voltage power tubes, which means it might be good for harp. Lower power means sweeter tone and less feed back.

The article offers a great many good ideas about where to get parts, how to salvage stuff to save money, even how to build a neat cabinet.

Even if you are not going to build this particular amp, it is worth while checking out the process. It may be just as easy to build a deluxe or bassman clone (I suggest looking at a tweed Fender Super Amp). 

 

Buy the Book!

I cleaned up my tab for Sonny Boy's Help Me and made it into a short book. There's a Kindle version for 99 cents, and if you buy the paperback you get the Kindle free.

Playing "Help-Me" In the Style of Sonny Boy Williamson II: A step by step, note for note analysis of some of Sonny Boy's Signature Riffs