I looked into this awhile back and bookmarked:
Paula Burch's How to Tie Dye
The site while fairly dated and looks fairly dated, has many great examples and how they were made. I'm still thinking about doing it possibly later this year, but then I'm afraid people would think I'm a hippie. I used to have hair down to my arse, so people who have known me for that long, would definitely call me one...