The Winx Club
This toyline got more fabulous with each wave... unfortunately for me, they made too many for me to keep track of... I think the series I have listed here is wave 2 or 3, they came out in 2006... after this wave they came out with the enchantix dolls, which were absolutely stunning, and quite pricey... too bad, because I'd have bought them if they were a bit more affordable!
The Winx Club started out as an Italian cartoon, and spread to America in 2004. There are things that were certainly lost in the translation, and I would love to see the original Winx Club cartoon episodes in Italian with subtitles! The toys were not far behind. There has also been one movie produced in 2007, and another is rumored to be hitting America by Christmas 2009.
Merchandise for the Winx Club is extensive... there are backpacks, coloring books, costumes, you name it... if you can conceive of it, it probably has a Winx logo on it! I don't know if there's any way to catalog all that!