From Printrbottalk Wiki
Kit assembly instructions:
Assembly Videos for printrbot Jr., printrbot, printrbot LC and printrbot+ are available.
| Printrbot Jr.
Portable 4 inch x 4 inch Printrbot
6 inch x 6 inch Printrbot with printed parts
| Printrbot LC
6 inch x 6 inch Printrbot with laser cut wood parts
8 inch x 8 inch Printrbot with laser cut wood parts
|Finished your assembly? Take a look at the Getting Started Guide|
Official PB Youtube Channel - 
Build images for Printrbox laser cut case for Printbot: Printrbox Build