For Windows users the quickest way to get Ruby running on your box is to get Instant Rails which provides you with a development platform right out of the box. Mac users can use Locomotive. If you're using Linux and don't know how to manage packages then install a GUI, shave your head, and pretend you actually like Macs.
If you're like me you will want to try Ruby before reading a more thourough guide or online book. Then maybe have a look at database access before spending some time reading a Ruby blog. There are a number of Ruby forums online.
Cheating at ruby
This Ruby cheat sheet is a 14 page PDF that will act as a quick reference. This resource website will also allow you to quickly develop your skills.