If you're going to the trouble of putting on a public event, you should probably think about promoting it in a way that doesn't, as they say, "suck." I could probably help you with that.
I make a lot of gig posters for bands, because that's something near and dear to my heart. And sometimes I make posters for other events—theatrical performances, charity events, even weddings—because there's a lot of great stuff happening in Northfield (and elsewhere, believe it or not!) that deserves a decent poster.
Get in touch at firstname.lastname@example.org if you want to talk to me about making a poster for you.