Hi: what about looking up "American Bandstand.com" ? There most be lots out there about this rock history theme. And get cut outs of Elvis and other rock n rollers of the time. Find 45 RPM records from friends. Hang them up- Get a record player- you know those old machines and have someone play a DJ for the event. I hope this helps.
We just did a "Rock Around the Chrsitmas Tree" theme for our volunteer Christmas party. It was a blast! I decorated the room in pink table clothes and black plates with a white bowl on top (To look like records or hubcaps) Wehad old 45 records hanging fromt he ceiling. We served rootbeer floats and cheeseburgers (crock pot to keep warm- adding the cheese as they took their burger) We had a bubble gum blowing contest and hula hoop contest and ofcourse played lots of 50's music! Have Fun!