www.birdingonthe.net has access to the Utah birding LISTSERVE. Recent sightings will be listed there, and you can subscribe in order to post an RFI (request for information).
You can likely access Utah trip reports on Blake Maybank's website...
The Matheson Preserve in Moab is one of the birdier spots in the area. Well worth an early morning visit. The few riparian areas in Arches itself can be productive, as would be the banks of the Colorado along River Road.
Best of luck.
Steve in Houston