It akes some research but I have been able to find providers who will accomodate most of my "kinks".  You may not be able to find one that will do all of them, but several would probably cover most.  Of course, they will be more expensive.  Porn stars are a good place to look, too.

I have many that tell me what they enjoy after I made sure who they are. I and manyothers enjoy kinky things.
Kisss
Dawn

The internet (and TER) is full of providers that are kinky. Try looking for someone who specializes in the experience you are looking for. I also believe if you are a regular with a provider you develop a certain amount of trust and depending on just how kinky it is she might go along with it.

You are probably not alone, but more alone than you thought.  I'm not going to touch "...how to get providers to explore their kinkier sides?" since that has been dealt with by the providers who've already posted on this thread.  I will say this though; the internet and TER has made it much EASIER, not harder, to find the women we want to "live out our fantasies".  If it's happening less often with you, take the advice of the providers' posts and get to it.  The internet isn't part of the problem!

Do a TER search and you shall find all the kink you can eat.

BBBJ, Greek, S&M, all these are to be found in the ratings. If role playing is your game that can be found out fairly easily as well.