Hey Joey,
Most legitimate massage parlors are just that, massage parlors. And anything beyond getting a rub down is strictly forbidden. If you were to become aroused during a session, that's usually enough to end it.
Depending on where you live there may well be parlors or individual sex workers that *specialize* in this kind of body work. You can usually find them in an adult paper or you might even find one online.
It's usually up to the individual exactly how the "happy ending" is achieved. It may consist of either oral or manual stimulation to orgasm or more. "Full service" is a phrase that's used to describe this kind of body work and the rates or "tips" are usually left up to the individual sex worker.
Some things to keep in mind... Even though this is a business transaction you are still dealing with a person, so be polite and respectful. You'll get a far better response if you keep this in mind. Don't go in all smelly and disheveled but don't put on a whole sh*t load of cologne or aftershave either, soap and water will do just fine. While you're at it, brush your teeth!
Don't be a total pr*ck if they insist on condom use!
And don't try to haggle about the price! That could very well get you tossed out.It isn't like this is "Let's Make a Deal" here so don't act like it.
A lot of parlors take a percentage of the stated "fees" so be generous and tip the sex worker as well.
Hope this answers your questions
Jim