Re: Any ideas on how to transport kayaks on a toon...
I have a ton of ideas, depending on how handy, creative and willing to spend time you are. It is an interesting question. Do you want to make them hidden? Do you want to travel with them there?
The easiest would be to either bungie them to the outside of the railings, one on each side. You could also create some sort of rack for them on each side using either some aluminum chanel U-hangers or PVC pipe.
It would be really nice if you could rig a hook underneath the decking and hang them under there. If you could lean over the front and catch something on the back of the kayak up under the deck, then lift up the front and hook it up under there, it would be out of the water and everything. Depending what you have back there, it would be easy to fabricate a rack that could stack them over the top of the motor on the back of the boat crosswise. I don't think you could trailer with them there, though due to the width of the boat and the length of the kayaks.
Post a picture of what your boat looks like and describe how important it is to you that it look 'professional' and we can come up with lots of ideas.