Tex--
i'm in a somewhat similar position. i'm 50 also and have given up on the road racing idea for long distances. a good bike is key, of course, but also is attitude. i get the impression you're looking for a few folks to ride with and in my experience that is not what brevets are about. the brevets i've been on all start in a cluster but pretty quickly riders get sorted out. although i may ride for a while with a few riders or even just one sooner or later we'll separate.
when i first got interested in randonneuring i went through the same stages as you. i did the research and eventually found a club. i thought i would enjoy the fellowship and advice of fellow riders but they are a club in name only. i only see these guys at the brevet events and there is no other contact in between. a good deal of LD riding is being by yourself so you might as well get used to it. my advice is to just get out there and start putting on miles and enjoy the solitude.
good luck and enjoy.
** mp **