again I have to post this site:
http://mymasturbation.com
Trust me, I"m in my 30's I was kinda getting bored with it all too, since I'm single way more often than I'm not. After reading this site, and seeing all the different ways people do it well.......... it was like a whole new world opened up to me, like "wow, I never even THOUGHT of that!"
Another question I would have is, and sorry if this is too personal - you haven't gone any new medications lately have you? I remember I was on Paxil for a year, and after I started it took a few months to be able to have an orgasm again, and I had to sorta force myself to keep going til it worked.
In any event, I hope I was helpful. Good luck.