Kenneth P from Denmark:
There are lots of diagrams in that book. I think it is a good read and presents a pretty thorough examination of the various stages of the power amp.
Randy Sloan used to publish kits of high quality DIY amps. I think if you dig enough you can find the schematics.
http://www.zusaudio.com/navigation/seal.htm
Also check out Nelson Pass DIY page for some really great articles and projects:
Amps
http://www.passdiy.com/amps.htm
Also there is much following for the kit based Lifeforce amplifiers from Hugh Dean if you want a very high quality amp with little else to do except get a nice case, buy a transformer and wire it up (i heard this amp and it is very good)
http://www.aksaonline.com/products_2_4.html
General:
Start off by reading the literature then forming ideas about what you think you want from an amp.
Get an idea about the case size (based on your other choices this size may change for increased heatsink area say.)
Sketch the mechanical layout of amp sections-
-transformers
-switches
-fuses
-rectifiers
-filter caps
-input circuitry
-approximate wiring
-output section
-input/output connections
once you nail down a design work from the schematic and build a BOM (bill of materials in excel or similiar) to keep your project sane. The BOM should contain every part in the amp, where you get it, how much it costs, who that vendor is, quantity needed...etc..
you will need to pay attention to:
how will you handle DC
how will you ensure stability (no oscillations)
how to protect against faults (dc, over current, thermal, input surges, you have to protect your speakers!!)
the devil is in the details but going through such an experience will give you much more respect for the makers of true high end gear. It is a long journey so be patient and keep an open mind.
If you happen to come across anyone from Dynaudio give them my regards. I love their speakers!