Just go by yourself. Some of the bands I like my friends haven't even heard of. So I've been to a few shows myself. Actually, I just bought a friend of mine a ticket to a concert I wanted to see last week. Turned out she's really interested in the artist and phoned her brother and a mutual friend from the show to tell them (because they like me love the artist) where she was. It was great, except now she wants to be more than friends even more.