I etch boards for some projects myself, but the reason I do it is because there is no professionally made board available for what I want to build. If you want to build a pimeta, just buy Tangent's board, at $7.50 it is an incredible bargin and it's way smaller than anything you can do with toner transfer. By the time you buy ferric chloride, copper clad PCB, glossy photo paper, etching tank, acetone for cleaning ink off, tinning solution, etc., you'll have spent way more than $7.50. Etching isn't going to save you any $ in this case.
If you still want to learn about etching, you should look around for other PCB layouts that people have published here and on headwize, or draw a layout yourself for something that's simple enough to do on a single-sided board. Try a Szekeres, for instance -- that's an amazing amp for something so cheap and simple. Or look through Sijosae's posts for lots of ideas to build on one of his layouts or adapt to your own.