Looking for the docs for the new ColdFusion Builder 2? Yeah - me too. I've always found that a bit difficult to find on Adobe.com. From the main product page click Customer Support to land on the main ColdFusion and ColdFusion Builder support page. In the right hand nav, click to expand Developer Documentation:
And there ya go. The install and using guide in both HTML and PDF. If you don't feel like clicking, here are links to the HTML Guide:
Installing ColdFusion Builder 2
Of course, you can always just visit the ColdFusion Portal where I've just updated the links.