I would seek other web developers at any number of public forums like OReilly Ignite, BarCamp, DevHouse, etc. For informal UI testing, you can even go to any c

I would seek other web developers at any number of public forums like OReilly Ignite, BarCamp, DevHouse, etc. For informal UI testing, you can even go to any coffee shop, show people your work, and ask them what they think. Often you can benefit by seeing a virgin user who didn't understand that action X lead to result Y. You could also quantitatively test your choices by pushing a different UI on some small percentage of users, and see how it affects performance or things like signing up active users. Certainly rely on your peers, but the best mentor is need. Solving a problem teaches so much.