Roscoe, as you know, is an area replete with fly fishing history and is one of the cradles of its development in the US. Therefore, it should be fairly easy to get help from one of the fly shops in the area (I know there is one in Roscoe).
Also, there are fly fishing clubs in that area too, which means if you find out when they meet and go to a meeting or two, you will be able to find folks who are willing to have you go fishing with them and teach (or mentor) you in trout fishing with a fly.
One final suggestion, when you go fishing in the rivers and streams around Roscoe (or just go to one of them and watch the fly fishers) and see some folks who are catching fish, wait until they finish and ask them for some help. My experience over 49 years of fly fishing has been that if you wait until someone is finished fishing a pool or run and then ask them for some help and pointers (explaining that you are new to trout fly fishing), nearly all fly fishers will help.