I thought the Management and Configuration Guide for the 25xx series switches was pretty good. If you don't have it already, it can be downloaded as a PDF from HP's Web site (it's about 5 meg - 400 pages or so). The VLAN stuff is in Chapter 9 - Configuring Advanced Features.
By default, the switch has 8 VLANs defined so you can get up and running just by assigning the proper ports to each one. You do, however, have to make some decisions about tagged versus untagged (you'll need tagged ifyou want a particular port to belong to more than one VLAN) and so on. Inter-VLAN routing is a whole 'nuther thing but it's covered in the manual as well.
Other than this book, I don't know of any HP-specific references.
regards,
paul