If you are into making over or just styling fashion dolls I have a couple of links for you.
These are excellent tutorials on doing Barbie's hair.

1. http://www.rebeccachulew.com/ezine/hairrescue.html &
2. http://members.fortunecity.com/customdolls/hair1_page.htm

The second link is a 2-pager. I found these some time ago and I would suggest that you save the pages if you are interested because they may not be around forever.