User Onboarding
User Onboarding is the process of radically increasing the likelihood that new users become successful when adopting your product.
The DIY Onboarding Repair Kit
Analyze your onboarding flow and find high-impact changes you can make NOW.
Teardowns
Let's learn some lessons from how popular web apps do it!
Here's the latest:
And here are some other recent ones:
QuickBooks 
Bitcoin 
Dropbox