Make your way to Jackson Hole WY. Once there procede on Hwy 191 through the park to the Moran junction and head towards Jackson Lake/Yellowstone. The Oxbow Bend turnout is aprox. 5 minutes down the road...you cant miss it!
Oxbow Bend is a prime photography location any time of the year but I like the Fall the most. There is a stand of aspen trees that just really brings the color into the scene. If your oportunistic and get some clouds above Mnt. Moran you are in for a great show come sunrise. Get there early though, this spot is not secluded and you will see many photographers here.