Donna,
Bergerac is in the department of Dordogne in the region of Aquitaine. You may try posting to the Aquitaine region board since this is the board for Centre France, a region north of Aquitaine.
http://boards.ancestry.com/localities.weurope.france.aquitai...or you could post to the general board which seems to get more traffic/helpful people
http://boards.ancestry.com/localities.weurope.france.general...I looked at the records for Bergerac in 1848 and did not see a birth for Jean Baptist Delbasty but maybe someone from one of the above boards has more experience and can find the record for you.