I went to a MP in the Roswell, GA area not to long ago for a massage with HE.  I was escorted to a private room, paid cash and was give a table shower/massage (which was great), but no HE.

What are the rules of engagement here?  What did I miss?

First of all are you certain that the MP you went to offers anything other than a massage?

The rules vary from place to place. Often a new customer will get nothing beyond a regular massage.  In most of the places I've been to, and it's been years since my last MP visit, you pay out front for the service and tip the girl in back for "extra service".  If all you payed was the quoted house fee it is possible that the lady assumed you didn't want any more than a massage.

There should be a FAQ on this site for MP.   Typically the first  payout (usually $60-$80) is just for a massage in private room for an hour.   That money usually goes to the parlor.  If you want anything more, you have to pay more.  You negotiate that with the girl.  

Try this: You pay the upfront fee, take the table shower, then you both go back to the room.   Talk to the girl while she's giving you a rubdown.  She may be worried that you're a cop, so try to get her to relax.  After about 10 minutes of small talk, stroke her leg, thigh, etc.  That's a signal that you want something more.  She may ask you directly or indirectly about what you want.  Then the bargaining will begin.  

Note: there are legit parlors that just do massage.  Check their hours--if they stay open really late (10 pm or later) then its probably a brothel.  If they shut down at 5 pm, probably legit.  Good luck.  --z

Some places just don't, but...

I usually leave a tip in a conspicuous place, usually the table where I leave my glasses, watch, etc. Just as with a regular provider, it is not often spoken of.

A first timer often doesn't get much, but usually a HE isn't too tough.

Try to get a read from the shower. Was it purely professional or did she get EVERYTHING squeaky clean?

Try a second visit with the same girl, if you like her. Leave a tip in plain view (try 50 for HE).

Definitely try a little hands on yourself to let her know you want more. Stroke the outsides of her thighs  little at first, or something that wouldn't get you killed if she doesn't want to do more.

Also, how is she dressed? The HE places they usually are dressed in a fairly sexy little dress that looks like it could go on/off easily.

You may find something on TER, so try looking here first.

Finally, I am sure that I can't mention the name here, but there is a web site similar to TER for reviewing "erotic massage parlors". I'm sure you and Mr. Google can manage. I saw four listed for Roswell.