I’m particularly fond of this subject, because I’ve been there, done that: a few years ago I suffered a catastrophic hard drive crash, with no backups in sight. (You can read the full story here: DriveSavers to the Rescue.) Believe me, the cost of setting up an effective backup system pales in comparison to the hours of inconvenience it takes to get your data back (and as a freelancer, my time is certainly worth money) and the cost of having your data professionaly recovered (for this service alone, plan at least $1,000 and go up from there).
After reading Joe’s book, I was able to identify holes in my current system and patch them (such as maintaining both a duplicate and an archive of my PowerBook, and then another copy of each). Here’s more information on the book, from the blurb:
Coming up with a reliable backup strategy might seem complicated, but in Take Control of Mac OS X Backups, backup expert and best-selling author Joe Kissell provides the straightforward advice you need to go beyond the false security of copying a few files to CD. Joe makes it easy to decide on a backup strategy that protects your data and enables nearly instant recovery, and he goes on to compare the pros and cons of each type of backup media, such as recordable CD, recordable DVD, tape, hard disk, and more.
Trust me, even if I wasn’t involved in the creation of this book, the $10 you spend now will save you hundreds of dollars later by avoiding catastrophic data loss.