She is a great singer, that I have just found on YouTube. Her music is similar to Avril's, pop rock.
Here are some of her songs, that I really like:
http://www.youtube.com/watch?v=Z7_r4BOgOwA&feature=related - I Like
http://www.youtube.com/watch?v=N7Fy_fx3Ryw&feature=related - Overdrive
http://www.youtube.com/watch?v=SUxhS-orXQU&feature=related - Because I Can
http://www.youtube.com/watch?v=SzEPzfoPpAE&feature=related - Teachin' Myself To Dream
http://www.youtube.com/watch?v=8Nea6hRweN8&feature=related - Snowflakes
http://www.youtube.com/watch?v=V6uCOgf0SoU - Lemon

Some of her songs may be a little slow but you do get into them. I think her best songs are Lemon, Overdrive and I Like.
You may have heard Overdrive in the film Mean Girls

Thanks! She is awesome, though of course not as awesome as AVRIL LAVIGNE!