Mexican Genealogy Research...where are the records?

Several years ago, during a phase of heightened genealogy invincibility, I offered to work on the genealogy of a friend. I was having such luck with my own I wanted to share the wealth. Little did I know that I was not quite that talented. See, my friend's family is from Mexico and settled in San Antonio in the early 1900s. When I first started my search it was before Footnote, the much more robust FamilySearch and the myriad of newspaper archive sites. So I found little to nothing on her line. I was able to find a few birth records from Texas and that was it. I was embarrassed and I learned my lesson: don't promise what you can't provide.

Cathedral of Monterrey, Mexico. Photograph courtesy of we work for free, wikimedia commons.

So after a few years I decided to try it again. Her grandmother had died a couple of years ago and I was able to find her obituary which was a major break in the case. With all the new record repositories online I was able to track her family back to Mexico. But here is where the trail runs cold. I haven't been able to find many Mexican records digitized. I'm not going to Mexico anytime soon so there will be no boots-on-the-ground research. I have checked out a book from the library on Mexican genealogy research and I am hoping that it will help me to find the records I need. I suppose the next step is to try and order LDS films...once again "old school" may save the day.