Marriage records are at the courthouse in Livingston. Birth records will have to be purchased from Vital Records department of Louisiana in Baton Rouge or New Orleans. None are posted on the internet that I know of. Louisiana Death Index,1900-1949 can be found at Ancestry.com. You might also try the following website. Death records before 1956 can be found at the Louisiana Secretary of State Archives Department.
http://pilot.familysearch.org/recordsearch/start.html#p=0What families are you researching in the area? I can do limited research of Livingston Parish records on the internet.