The Photographer's Toolbox:

Free Photography Classes Online – LIVE classes taught by some of the best
photographer’s in the world.

My Favorite Lens – Incredible image quality for under $150.

#1 Photography Book on Amazon –  Comes with over 14 hours of online training videos. Over 250,000 readers.

Photo Inspiration – Search photos based on which camera they were taken with.
 
500px – Another source of inspiration for your next great photo idea.
 
CreativeMarket – HUGE collection of Lightroom Presets.
 
Flickr – An endless source of photo inspiration.