Useful Links:

Google Analytics:
You will definitely get your money's worth

Moz Blog:
Previously known as SEO Moz. These guys know their stuff! A great resource for all things marketing.

Hubspot:
A great educational resource

KISSmetrics:
A blog about Analytics, Marketing, and Testing

Post Advertising:
A fun blog about Marketing and Advertising

Springwise:
Did I mention I love innovation?

TED:
These talks are valuable, entertaining and inspirational

W3Schools:
Every marketer should learn to code