I recently configured a multi-camera live streaming setup in the studio here at the DVEstore. In the video below, I run through all the pieces and how they work together. Below the video, I've put links to all the various parts and pieces so you can get more details and prices.
There is a section in here about connecting a Macbook Pro to an ATEM Television Studio HD, as well!
Note: Some of the products have been updated and links are to the currently available versions.