Building amps probably is easier than designing a good speaker system, in my opinion.
Tube amps are popular and there are many circuits that can be picked off the web for both solid state and tube that can provide a foundation for a great sounding amp.
There are also many books available on the subject that are worth looking into. Having a good understanding of basic electronics is helpful. From there there should be a wide selection of books and articles on the web that can flesh out your knowledge.
Express PCB is a good place to get boards made (they have free layout software).
I would give it a whirl and start by reading everything you can, then the path will seem a little clearer.