For music, I had brought my stereo out, and we set it up with two extra speakers. It was more than we needed. We thought it would be so nice to have someone show the guests a few steps of an Irish jig or a May dance or something. The music was played on a small tape machine hidden out of sight. Contact them and ask if they have a group that performs.
People often know people who know people.
Through the staff at the Renaissance Faire where we held our wedding, we hired a woman that played hammered dulcimer. Since the demand for Ren music is small, their prices tend to be low. You might try seeing if there's a local English Country Dance or Contra Dance community in your area. Word of mouth is the best way to find a band or anything else for that matter. Ask couples or parents who have recently had a wedding.