Manufacturing in China vs the U.S.: for my company's Kickstarter project, the U.S. was about 5x more expensive. (It's a bit different for electronics).
However, after flying me and my co-founder to China, living there for a month to work out all the kinks in the process, then the incredible cost of shipping and customs taxes (has to rush ship for Christmas of course), I'm thinking the U.S.would have been a better choice (at the small volumes of 1000 per batch we were doing).
Now, if you are making 50,000 or a million of something, then China is definitely the way to go. But for small batches I recommend shopping around U.S. factories... They're pretty desperate for it at this point.