Having converted Losing it from Movable Type, which is based on Perl, a language I’ve tried to learn a few times, but gave up on as it made my head hurt too much, to WordPress, which is based on the significantly less pain-inducing PHP, I decided it was time to learn more about the underlying language….
So, I bought a book. There are loads of PHP and MySQL books around, ranging from the dreaded “For Dummies” series through to huge doorsteps that I know I’d never get round to reading. After much browsing and dithering, I settled on the Visual Quick Pro book. Relatively cheap, works from basic examples (though assumes familiarity with (X)HTML and preferably some basic programming experience) and has loads of illustrations, so you can see what your work should look like. Seems to be as good an introduction as any of the books I could find.
 I just can’t bring myself to even look at the damn things. Hate the name, hate the “reference for the rest of us” attitiude.