I don't believe there is such a list - IIRC RoF just tends to identify them using whatever Windows tells it, which is one reason why changing controllers (or sometimes just plugging them in and out) can screw up your controls setup (because Windows changes the IDs it assigns to the controllers).
The easiest way is simply to go into the RoF controls setup screens, pick some command you want to assign to that joystick (e.g., pitch), and move your joystick accordingly - you should see RoF fill in the relevant cell with something (e.g., Joy1 Y-axis), which will tell you what RoF thinks is your joystick. Every other thing you try to assign to that joystick should get filled in with the same Joy1 or whatever the first one did. If you want a list of everything (all the RoF commends) you have already assigned to that joystick, I think you're going to just have to keep up with it and make your own list as you go along. But maybe I'm missing something - I'm away from my RoF PC so I can't check anything about it here.