I recently put a Saris hitch rack on... I always had Thule racks before this... I really like it...
http://www.saris.com/p-298-thelma-2-bike.aspx Obviously you're not going to hitch your car, but I've been impressed by Saris, in general, so far!
Um... 50 is nothing! I'm been really surprised by the more aged individuals kicking some serious ass on the bike rides!!!
You'll have to let me if you ever end up in the Tampa Bay area...I'll give you the skinny on the St. Pete Bike Club rides! Great group rides!