Seeking information on Grandparents in State of Jalisco, area of Los Altos

Hello! My name is Ann Marie Gutierrez and I am seeking info on my grandparents and great-grandparents whom I believe where from the area of Los Altos de Jalisco. Specifically around San Diego de Alejandria, San Julian, Purissima or what one individual called, "Los Llanos," de Jalisco. My Grandfather's name: Exiquio or Ezequiel Gutierrez, b. 1869; married Maria Teresa Gomez or Guerrero, b. 1871 were married around 1886? Children of that marriage were: Ricardo b.1903; 2) Franciso, b. 1907; 3) Jose, b. 1909; 4) Maria Socorro, b 12 July 1912. Of course, these are approximate dates since I have not found any documents for them. I would appreciate any assistance I can get on suggestions how to start my search or if anyone is familiar with that area, perhaps they would assist in letting me know what is the name of any church (s) in that area. Was there a certain town that kept civil documents or info?--- any and all info would be welcome. Thank you in advance for any assistance you may provide.
Ann Marie Gutierrez
Chicago, IL