Tickets for the Philadelphia, Boston and Denver shows are on sale now; tickets for the Glendale, AZ, stop are currently available only to members of Lavigne's fan club, but will available to the general public on Saturday (6/26), according to promoters.

Released in late May, "Under My Skin" sold more than 380,000 copies during its first week in stores, and debuted at No. 1 on The Billboard 200 album chart. The set features the cut "Don't Tell Me," which has been riding Billboard's Top 40 Tracks chart for 15 weeks, and currently sits at No. 15.

The album is the follow up to Lavigne's 2002 debut, "Let Go," which hit No. 1 on The Billboard 200 album chart, and has sold more than 15 million copies worldwide, according to a press release.

"I grew up so much in the past two years," Lavigne said in a statement. "I've been through a lot, I've learned a lot and experienced a lot both good and bad. These songs [on "Under My Skin"] are about all of that, and each is very personal to me."

Lavigne, who co-wrote the new album's 12 tracks, collaborated with producers Butch Walker (of the Marvelous 3), Raine Maida (of Our Lady Peace), Don Gilmore (Linkin Park, Pearl Jam), Ben Moody (formerly of Evanescence) and singer-songwriter Chantal Kreviazuk. Lavigne's guitarist, Evan Taubenfeld, co-wrote much of the material with her.

On June 20, Lavigne, an Ontario native, won the 2004 MuchMusic Video Award (MMVA) in the People's Choice Award category of Best Canadian Artist.