I believe that last summer field & stream ran articles on kayak fishing for the june and july issues. Additionally you can pick up some books on kayak selection. Can't remember an titles off the top of my head, but I know there are a few books out there specifically regarding how to select your kayak.

I couldn't give you any specific recommendations for what type to select for the McAllister Creek area due to the fact that you are in an estuary with tidal influence. NO kayak is capsize proof. However, if you are concerned about safety then a sit on top is your best bet because you can easily remount after taking a dunk in the salt. Also, wearing neoprene waders will float you but i don't think it'll save you from the sharks. If you do not plan to travel very far in the area, a polyethylene hull will due the job for the cheapest price. Overall you want something that will be seaworthy for those days when the glass surface turns into swells and you get caught unawares.

You should check out Olympic Outfitters, they have an "SUV" kayak for sale, it's the Hobie Mirage Outback. Rod holders are built into the hull so you can tote up to 4 rods, two fore, two aft. Should be enough room to hold a good sized nook beneath your feet.

Another idea is to go to Boston Harbor and check out the kayaks there.