Check out their tour dates and how to purchase tickets: link


Also:
The American Cancer Society is teaming up with legendary American rock band Chicago to create the ultimate fan experience that will also save lives from breast cancer. For all US concerts open to the public in 2010, fans can bid on a VIP package that includes the opportunity to sing the hit song "If You Leave Me Now" onstage with the band during the concert, 2 front row or premium tickets, and a backstage meet-and-greet with Chicago.
Proceeds will help the American Cancer Society fight for every birthday threatened by breast cancer in every community - by helping people stay well, helping people get well, by finding cures, and by fighting back against this disease.
Bid to win the only VIP fan treatment from Chicago that not only gives you the opportunity to rock with the band, but also helps create a world with less breast cancer and more birthdays.

Check out the details and how to bid by clicking the link below:

link