'Nuther reco for mountain bike shoes and clipless platform pedals. Mountain bike shoes have soles you can actually walk like a normal person, unlike roadie shoes. Pair them up with mountain clipless platform pedals. Several models from Shimano, Crank Bros, Time and others. They allow your foot to be connected to the pedal while not clipped in, then the extra platform area provide support for your shoe than a normal clipless pedal suited more for skinny racers.
The pedals you can find online, pick one you like. My preferred pedal is the Time ATAC in it's many flavors, platforms included. For the shoes, you'll need to go to a store to get fitted unless you've got the time and patience to do returns and pay for shipping. If you got a REI in your area hit them up. They usually have a cycling section and selection, decent customer service and returns policy than you LBS.