Looking for Info on Lavergne Family Descended from Louis DE Lavergne

i am looking for info and family i dont already have on louis de lavergne married to marie anne simon. i can find info on louis but not much before him. i can also find the the name of casimir lavergne as the son of eloi lavergne, but i stops after that. louis de lavergne was my 8th great grandfather on my dad's dad's side. any ideas? thanks, carol