This is from the STP MySpace bulletin just now:
The following dates have been added to the 2008 tour!
July 05 - Indianola, IA @ National Balloon Classic Launch Field (General on sale Friday, May 30, 2008 @ 10am CDT)
July 31 - El Paso, TX @ El Paso County Coliseum
The following presales begin THIS THURSDAY, May 29th, at 10am local venue time:
July 31 - El Paso, TX@ El Paso County Coliseum
August 23 - Alpharetta, GA @ Verizon Wireless Amphitheatre at Encore Park
They are still online so keep your eyeballs open! I bet Akron's tickets might be available tomorrow morning also.