I sometimes answer questions on StackOverflow, and I find the same questions keep coming up time after time about Subversion, and source control in general.
After my last mammoth answer I'm going to dedicate a section of this site to source control, mainly with a subversion flavour, but much of this will apply wherever you come across it.
I'm going to go with Eric Sink here. No-one teaches source control, everyone's left to work it out for themselves and it's darn near criminal. Schools, Universities, even workplaces themselves all fall miserably short on getting some basic ideas out there that make everyone's life much easier.
Eric's got his tutorial, which is an excellent start. It's flavoured around Vault (which is what he develops) which is fine. This book is flavoured around Subversion.