Gas leaking from top of gas tank?

Drove the Barracuda and filled up drove about a mile home. noticed gas dripping it looks like from the top of the gas tank. has been dripping now for about and hour and not really stopping maybe slowing down a little. any ideas? also gas gauge has not been working but all other gauges working fine. also once I remove tank should I go with new and where do you find them. thanks for any help.