I am one of those. I'm looking for others...it seems there are a few providers who welcome this activity and I'd love to try them out. However I'm not sure how to find the other guys. If this is something you might be help me out with, let me know. Of course, more details can be discussed later.

Either you bring the other guy or she does.

I think the best way to to this is to pick a provider that you have already seen and then find someone else who has reviewed her (positively, of course) as well.  A bonus would be for it to be a guy you have met at a M&G or something.  Everyone having some history with each other can definitely make it a better time.  

If you don't want to reach out to other guys, then you can ask the lady to bring someone.  I would recommend seeing the lady one on one first.  Always better to make sure you have some chemistry like that before you bring in a third party.

MFM is definitely on my wish list.
And I agree with Waterclone ion hooks to proceed.
Good luck

Check out www.newyorkgangbangs.com

Gangbang/orgy parties.

Go to Upscale place   and meet there 3 man .. I am sure if you be flirting with you woman,.. and she while kissing with you will flirt with eyes with other man ... and she can pick UP any any any sexy man .. I  always have those just as soon as I enter let say W hotel bar  asking what I drink .. if I  be with man there who wants invite other man .. it is more simple to do then you think .. of course  it be more simpler if you ran in to European man ..  here he will offer you himself :)
lovers .. it suppose to be FUN !!! let I share my story how  fist time I did  two men at time .. I had BF on work and it was national holiday  and we went to drink and dance .. and while we were seating  kissing  I did notice other man just cant hel himself but licking on my bra's brethel .. and of course we  danced then with him .. then we invited his to our table and both men was caring about me giving  Champagne  feed chocolate feed grapes ..  both touched me under the table .. people looked at us yes .. but smiled ..and it was giving more adrenalin.. we acted as all we are lovers .. I was on the  heaven form attention of 2 ..
.. then we went to my place .. and I invited them both . we danced 3 of us...  one kissing from front nd other kissing  back and rubbing butt checks .. then .. then .. I just do not remember the I stared feel myself as on cloud - cloud of 4 hands  2  tongs and  2  cocks ..I write more later
 I do it often  OFTEN!!!   but I need tell you yes it is NOT ONLY about chemistry it is about TEAM work for MEN... not allof them can work as a team when with woman - pulling on him  only not letting other man  do  it  too so  I need keep it always   even .. but in  hard ore sex I can forget it too .. so  ones who fucks the most he get the most ..  if not team work .. so men it is can be well done mostly with European males. for 10 years in states and   doing escorts here as 4 years I never been with functional american MFM . still want find it  I mean FUNCTIONAL when it is NOT about vagina cock mouth ass   vagina only
it has to be LOVE between us .
and it is easy ..if you are human and have  soul ... sometime it is very hard  for men not eel shy .. and again find europeans .. or men  or women .. it be better .

I would definitely be interested if you can find a willing provider!

What about reverse gang bangs =) 1 guy and multiple girls?