Yes, there is a bar in the airport (Jet's Bar), and a restaurant/lounge area where you can get some food. The food zone is quite large. There are also lots of shops where you can get little things you may want to remember your trip by, and a bank to exchange money.
Here's some pictures...
Belize International Airport
http://ambergriscaye.com/pages/photos/502.html
Jet of Jet's Bar at Belize International Airport
http://ambergriscaye.com/pages/photos/777.html
Outside waiting area at Belize International Airport
http://ambergriscaye.com/pages/photos/412.html
Leaving Belize International Airport and heading home
http://ambergriscaye.com/pages/photos/397.html
