Back, when Jesus was born, shepherds weren't like farmers or shepherds today. They were the outcasts of society, people who weren't welcome in the town or anywhere really. They were smelly and poor and left out. Isn't it wonderful then that the first people who hear the news about Jesus being born are the shepherds! The angels don't tell the King or the leaders of the town but the very people who have been left out of everything and live on a hillside with sheep. God wanted everyone to know about the birth of His Son and so tells the shepherds because He knows they will get very excited and will be willing to run straight to see the new King, telling everyone they meet on the way!