I know my sister always dyed her hair in many different colours when she was in highschool (blues, purples, greens, etc.), and always used the Manic Panic stuff. Lates shes been using different, i'll see if i can get the name from her if you like.

I also found this site (note: it has a painful layout to look at), that seems to have a lot of links to different hair dye companies --
http://www.zyra.org.uk/hairdye.htm