In 2004 Katy Perry began working with the production team The Matrix (perhaps best known for work on Avril Lavigne's self-titled debut) as an in-house vocalist. She also soon worked with producer Glen Ballard (the man behind Alanis Morissette's Jagged Little Pill) on an intended solo debut album. Despite being featured in Blender magazine as a "Next Big Thing," both projects fell apart.
The Sound of Katy Perry:
Katy Perry's lyrical wit has been likened to that of British female soloists Lily Allen and Kate Nash. However, her music is closer to the pop-rock of Avril Lavigne. The elements add up to a spunky, sassy approach uniquely Katy Perry.(http://top40.about.com)