At the Silverstone Classic they had Pink Floyd Reloaded - A German based tribute band who were tremendous. I think they would go down a treat with an LM crowd for a great Friday night concert.
Whilst I have never bothered about seeing a band on Saturday night at LM I do think that if you strip away all of the extra events that go on at the weekend eg the parade, ferris wheel, the village activities, the museum, the antics,....... and the band, the event would become sanitised and lose a big part of what makes it special for all of us, including those that only go to watch the racing.