Pharmer.org

 Its going to be hard to find what you are looking for. As far as I know there isnt a good mexican pill id site/book out there and for that matter there really isnt any for most other countries even much more developed ones such as Canada or the UK. Im pretty sure that like most other countries of the world except the USA there prescription drugs are prepackaged in blister packs, so it will have what the medication is suppose to be written on the package. I think a lot of what you will be able to get really easily OTC or through crooked pharms/docs will be Tramadol,Codeine or Neo-Percodan. I wouldnt go there expecting to get Hydrocodone,Oxycodone or Morphine without some form of a "hook up" just like here.

 I can give you one piece of advice, Neo-Percodan does not contain Oxycodone like American Percodan. Neo-Percodan is basically Mexican Darvocet. 

  i went there and u can get a precption from a pharmacist for about 10.00 xanax comes in a sealed bottle peracodine usually comes in a carboard container 10 of them are about 50.00 if u have a empty bottle of them just put them in that and carry the precption that thay give u to have them. if u do not have a script. when u go through customs in the usa and they find them they can and do send u back to mexico to go to jail there have u ever watched locked up abroad  be very carefull mexico loves to arrest  americans just for the money to get u out. but u can take them while in mexico with no problems.

Oh yeah!!! Locked up Abroad on Nat Geo man.... INSANE show. My two fav are the girls who went to Peru and the two guys who went to Venezuela!! I love those ones. Insane how people go there and lie and convince themselves they are doing something legit when they are smuggling! hahahahahha.. Insane show. And oh yeah the one about the dude on the bike going through Columbia!!!!