Does anyone have a idea on how to obtain hunting regulations for Mexico?

Try one of the outfitter's websites, they may have them listed on-line or you could call an outfitter. I know Jim Shokey has a lease down there, should be a bunch of them.

I would assume if you hunt Mexico you do it with an outfitter, besides isn't it almost all private land?

No, it would not necessarily be a traditionally guided hunt. I have State-side friends who have relatives in Mexico with private property.

I'll check the traditional guide websites more closely in the meantime.