-- Last Updated: Jul-24-12 12:35 PM EST --
Thereare groups that do tours (although they might be pricey b/c they include the cost of the kayak).
Also, there is a Massachusetts Audubon in Wellfleet that would be a good source of info (they do group paddles throughout the season) - and Goose Hummock paddle shop in Orleans are very nice people.
There is also a Craigslist Cape Cod site. Not sure how effective it would be, but worth a look!