Founders Brewing is a great place to hang out in GR and there are certain nights where they have free entertainment as well. Here's an idea of what they offer:
Thursdays
-Free live music
April 25th 9:30pm
-DiscFunktional Sunday
-Local DJ "The Boogiman" will spin a cool mix of funk, soul, and rare grooves for listening and dancing.
It looks like Sunday nights usually have free entertainment as well as Thursdays. I'm just a little late in the game. Sorry. But there's still time to catch a few more shows.