91 Pontiac Firebird - oil pan

I have a 1991 Firebird 3.1L Auto I just recently scraped the bottom of the car on the highway and now its leaking motor oil it looks like the bolt looks really bad and it has a little hole under it where most of the oil is leaking. I was wondering whats the cheapest way to get it fixed or is there anything I can do to keep it from leaking

thanks