Mandrake's own documentations are actually superb. Available for download on
www.mandrakelinux.com. They are not the most detailed but when I first started with linux, I found them very helpful. Not too much detail but enough to get a grip on what's going on.
Don't worry about them being for 9.1 and not for 9.2. At the command line level, even the documentation for 7.2 will be quite adequate.