The Yellowstone River is the river to fish right now in the Bozeman area.  Although the fishing can vary from day to day it has consistantly

The Lower Madison river is still under Hoot owl restrictions and I would say they will continue until Sept. 15th.  The Upper is starting to turn on but still

In my opinion the fishing doesn't get much better then it is right now on the Missouri river.  You can pick which technique you want to fish and have success at all of them. 

The Gallatin and East Gallatin are fishing great right now.  Overcast days have been the key for great dry fly fishing.  The mayflies have been coming off after 1pm.