I used to publish a zine called The Inner Swine, which was pretty successful, for a zine. Back in 2005, it was suggested by Clint Johns at Tower Magazines that I put together a book of zine-making advice, with the idea that Tower Mag Hell would print and distro it.
We never got that far, but I did actually put the book together. It’s a little outdated (heck it was probably outdated when I put it together, since I was born a curmudgeon), but still has some good ideas in there, I think. You can read it online here. You can download a PDF of it here.