Those are some great resources! I do a few things for my site. I have a clear cling on my car (just added this LOL) . When acting as a vendor for a local store, I put everything together and use hangtags I make myself at home on the printer. I attach them with grossgrain ribbon and they look great. In addition, each hang tag has my website on it as well as more info about what I sell.
When I sell on eBay I always include a business card and note with more information.