Seems I get quite a lot of hits from people looking for a sackboy knitting pattern, so to make your life easy… the pattern I use is by Alan Dart, and was published in Simply Knitting and The Sun On-line.
It’s a PDF, so simply download it, print it out and get busy knitting
UPDATE (12th Jan 2014) - Doing some housekeeping, it seems The Sun is now a subscription service and I suspect the pattern is hidden behind a payment. The pattern was also available for free on-line at LittleBig Planetoid.
UPDATE (9th Jan 2015) - Unfortunately, the pattern no longer appears to be available from The Sun and LittleBig Planetoid appears to have gone off-line. Doing some digging it is available in the web archive here.