Bookmark m.disneyworld.go.com/dining in your mobile browser and you'll have a pretty good resource there. You can even book dining reservations from a link on that page.
A note on using that mobile site to make reservations on the go: The pages time out pretty quickly, so I would recommend getting somewhere you can stay focused so you can complete your reservation quickly if you're doing that. I lost a day-of Garden Grill reservation because I started my reservation while waiting outside a restroom for my husband, then I put my phone in my pocket for a minute or two until we got to a bench, but by then I was timed out. I had to start over, and then the opening was gone. So act quickly if you're making reservations on the mobile site.