Frankly, I could have used a post like this myself after my recent trip to NYC. Unfortunately I always seem to go for fashion first, and my feet suffered BIG TIME. I think my blisters have blisters. Lol.
Anyways, the first shoe that came to mind are Soludos flat espadrilles. They are a celebrity fave (seen below on Kate Bosworth and Rachel Bilson - photo credit) and affordable at only $26-$28 per pair. Although I can't vouch for their level of comfiness myself, I've read good things about them online, so I think they'd be worth trying out!
If you're interested in purchasing a pair, here are a few options below - click on any photo for more info. Shopbop also has a pretty good selection HERE - don't forget to use your Ebates!