One of your first stops should be Sedona Oak Creek Chamber of Commerce. Here, you'll be able to find your bearings and get some great ideas before you start exploring.
You'll be spoiled for sightseeing choice when in Uptown Sedona. Sedona Chamber of Commerce Visitor Center is an ideal place to begin here, but there are loads of other worthwhile attractions to consider. Chapel of the Holy Cross, Bell Rock, and Slide Rock State Park are near the tourist information center and will round out your day nicely.