Hey Jess, sounds like you're covering all things...I think most of us have a drawing for a free massage, which you could do as well, or you could buy a gas card or a wide variety of things.
I buy registration slips from InstyPrints, 5 pads of 100 for 3.50, but you could make your own to customize them like mentioned above. Having them all attached is nice for being outside. I use a big vase instead of a bowel or basket. I don't know if it matters what the vessel is.
I find that people will give me their address but not email address. The slips have a line for email. I use anywho.com to reverse lookup an address if only a phone number is left. Sometimes those that only leave a cell phone number will be a winner, and if they come in...then I have their address. If they don't come in, then I don't want them for a client. :wink:
I think a clipboard with a sheet made for signup purposes would work great. I like the spiral notebook and email sign idea too!! mick