Tony,

I’ve sailed a few kayaks. Your 12 footer may just work fine. You usually want a longer boat for more speed. It is better to have a rudder. The simplest sail is just for downwind (I.E. with the wind to your back) I have seen three sided sails fitted to a hinge just in front of the cockpit. Two small poles are sewn into pockets in the sides of the sail. This rig allows you to lay it down on the fore deck when not in use. Sheets can be rigged to the stern of the boat to allow some ability to steer the boat with the sail. When the sail is up it is an upside down triangle with the point on the deck. I have seen kites available in catalogs to aid a kayak going down wind. Sit in the cockpit and fly a kite and the boat will follow.

If you really want to sail you need a leaboard. I built a sail rig for my Chesapeake Lightcraft, Mill Creek. The plans are available from at www.clcboats.com. I used wooden poles designed for use in closets to hang hangers on for the mast boom and spar. I sewed my own sail form a Sairite kit

My biggest complaint with sailing a kayak is the neck strain sitting in the boat with my head cocked to windward. It is nice to get out of the cockpit and sit facing the sail. If you really want to be inspired look at some of the canoe sailing sites here’s a good place to start: www.newsroom.com/boatworks/sailingcanoe.html-ssi