When I was trying to figure out whether the GH f/f I'd bought years before would actually work for me I tried setting up a fitting appointment just to use the local shop's fitter's time to help me figure it out. They basically wouldn't do it (they did give me free advice), they set up the fit just so, and that's it. YMMV. it's a small shop.
If you're just looking to figure out what frame size you take in general, I'd just go to the best local bike shop and tell them you aren't sure what size you take. They should size you for bikes they sell. Angles matter and all, but it would at least give you something of a ballpark figure to work with.
Honestly, if I were you I'd go ride a bunch of bikes and see what you think. Maybe something with scream out at you.