starting problem 65 polara

im stumped.
i put a new starter relay on the car and still nuthing, the only think that works on the car is the horn,
it also might help to tell you that when i brought the car home after i put a new battrey and ground on it, the headlights and intior lights worked, but i didnt have a key to the car then, every thing went dead when i put a new key tumbeler in the car so i would have a key for it, thats when everything wh=ent dead, im stumped please help.
also im not very good with elc parts names so any photos or discribinin of what im looking for would help alot
it would be greatley praised,
o and the car is a auto