If you need an excuse to go to Sedona other than the beautiful red rocks and the art, try the wine. You have time to schedule a trip for the winefest the end of September. You can only drink so much wine, so give yourself time to go on at least one of the jeep tours.
2012 Sedona Winefest Weekend, September 22 – 23
"By Sedona.biz Staff Sedona AZ (August 24, 2012) – The annual Sedona Winefest will attract wine lovers from near and far for an opportunity to taste only ..."
http://www.sedona.biz/arts-and-entertainment/2012-sedona-winefest-weekend-september-22-23/
The wine fest is at Airport Vista. If you plan your visit to when the sun is going down you have the chance to see one of the most beautiful sunsets. That doesn't happen all the time, but when it does you know you're in a piece of heaven.