What do I need as far as documentaion to get into Mexico if I am an american citizen?

Driver license

you just need a picture ID and a birth certificate Report It

Until 2007, which it will be manatory, you must obtain a pasport to enter Mexico or Canada.

Drivers lisence and pass-port, went to Baja, Mexico two years ago to do some Blue Marlin fishing.

Either a passport, OR a drivers license ALONG WITH a birth certificate. You have to have two state issued ids or a passport, not just a drivers license. And if you are divorced and your license not changed yet you have to take your divorce papers. Been there done that, have fun!!!

A driver license and a copy of your birth certificate

This is a Manzanillo question so I assume you are flying. Ask your airlines what's required. They won't let you on the plane without it.

Yes .. passport and/or drivers license and notarized copy of your birth cert.

Starting 2008 you can leave the country without a passport ... you just may not be able to get back in.

passport