Some of my favorite light lures for trout fishing are the Phoebe and the Panther Matrin. Both attract trout like you could not imagine in streams. I've gone out more than once and limited out using just these two lures. Now there are some limitations to using ultra light spinning gear. It is best to fish the pools that you find in the stream and deeper portions of the stream so that you can keep your lure at a depth that the fish are feeding. If you try casting your lure into extreamly shallow water all you are going to do is get hung up on some rocks. Shallow water is the one place where fly fishing will really out performs ultra light spinning gear. However, fish love the pools. If you find a decently deep pool and catch one fish keep casting into the same pool, chances are there are a few more hungry trout just waiting for something to swim by.
If you have never tried ultra light spinning for trout I'd recommend you give it a try. If nothing else it's a different way of fishing for them that you might find works for you and it is pretty cheap to start up!
-Paul Nicolucci