By plane
Moab's Canyonland Field Airport (http://www.moab-utah.com/...) has commuter service to Denver. Bookings from beyond Denver can be ticketed with United and Frontier Airlines to reach Moab. Moab's airport code is CNY. Ground transportation between Moab and the airport should be reserved in advance.
By train
The AMTRAK train has a whistle stop in Green River, Utah GRI. Combine the trail with your flights into Salt Lake City UT, Denver or Grand Junction CO then reserve a taxi or shuttle service to travel 52 miles to the town of Moab.
By car
If you are approaching Moab while driving west along I-70, use Utah Route 128 for the beautiful scenery. About 10 minutes past the Colorado-Utah border is exit 214 on I-70, it is marked as "Cisco". The landscape at this point is extremely dry, slightly hilly. The road is narrow no shoulder, and somewhat curvy, and it's about 80 km to Moab. About half-way, the road narrows, meets and then crosses the Colorado River, and the remainder of the trip is spent with the river on your right side and spectacular canyon walls surrounding you. This piece of pavement is one of the best drives in North America. Optimal times to take it are the morning ~9AM or afternoon after 3PM for the light -- do not drive it at night you can't see anything and it is more dangerous -- use US 191 instead. Watch for traffic, particularly bicycles as you approach Moab. The urge to rubber-neck is extreme, and needs to be resisted: be a passenger if you can. Eventually, UT 128 ends at US 191, a few minutes north of Moab.