from a hobby point of view... It is just not talked about for some reason at least in this part of the world (so ca)
Next prostate milking is different than prostate massage and also different that a prostate orgasm.  

Many FBSM ladies offer some form of prostate play you just need to ask (even amps provide the service)
Just about All tantra ladies offer the service since it is a traditional tantra ritual.  Just search Tantra

And finally madame Patricia clams to be the queen of prostate massage but I have never experienced her touch

good luck and keep learning