Any 3D Printing for Dummies tutorials out there?

 From:  paulrus
I'm mainly a 3D animator, so when it comes to real-world measurements & manufacturing, I have no idea what I'm doing.

I'm really interested in 3D printing, but I have no idea where to start. I've read that you need to make sure your object is seamless, and it's a good idea to make them hollow to cut down on materials used, but beyond that I have no idea where to start.

For example, I've seen things like chains or rings linked together that were 3D printed. How can they "print" objects that aren't connected, yet are intertwined?

Also, how do you figure out what size to make the object? I mainly work in Softimage for animation & there's no real-world measurement system in Softimage.

I'd love any pointers or links to tutorials for people who know nothing about machining & manufacturing.