Keep your eyes open for single day schools, some tracks will bring in either current or old pros to teach, and there is usually all different ages of people.
I did a week camp last summer at the Thompson's track in Brigden. In a way it was fun, but it was WORK. Drills basically all week, taking away our clutch levers, doing laps without sitting down, no rear brake use etc... But, the first weekend back to racing at the end of that week, I was rippin! Hard part is to make yourself do those drills after the school.
I used to deal with arm pump, and my first ride each season I get a bit during my first day out, but after that I'm fine. I can do a 30 minute session at Gopher doing ~2min laps without arm pump, but I'm bagged after for a little while.
I think spending time on the bike and getting comfortable on it helped to get rid of the death grip, as well as working out all the time (cardio, plyo and some weights). Sometimes it's a mental issue as well. Legs are huge in moto, once you get them working like they need to be, it lessens the load on your arms.