Dan, it sounds like youve got all you need for a club! go ahead and form it, elect officers, setup a few club runs get the club registered with IMPBA and Register/Insure your pond with IMPBA and youre set!
When we started Charleston Model Boaters, it was only a small handfull of us, barely enough to elect officials and it turned into and very nice club with 15-20 members, (dont know the exact number cause now im in germany). You have to have ambition and club members who are willing to pull there fair share of the weight. Its not an easy thing to maintain, and someone always ends up doing more work than others, but if you love the hobby enough you will be able to make it throught. Most of all, have fun, Ive had more fun a 10-15 boat club races than at most big events. If it stops being fun, it pretty much.....well.....stops!
~ James