Home Pizza Making is the absolute best online forum for home pizza making
Pizza School NYC online and in-person classes and team building events
Forno Bravo has DIY oven plans and general info about wood-fired cooking
Serious Eats publishes recipes and useful articles about home cooking with a pizza micro-site
Scott's Pizza Tours teaches online home pizza making classes for groups and individuals

Professional Pizza Training
North American Pizza & Culinary Academy hosts professional and amateur cooking classes with certification 
International School of Pizza is Tony Gemignani's professional pizzaiolo training school in San Francisco
Pizza Academy Foundation trains individuals on the art of Neapolitan pizza making
Goodfellas Pizza School NYC hosts one-on-one instruction for aspiring pizza makers
Pizza University brings guest instructors from top pizzerias to teach small classes  the basics of opening a pizzeria

Pizza Tours
Scott's Pizza Tours leads pizza tours and online classes, based in NYC
Chicago Pizza Tours takes you beyond deep dish to explore Chicago's pizza scene
Milwaukee Pizza Tours tours Milwaukee's unique pizza landscape via bus
Boston Pizza Tours explore Boston's historic Italian North End
A Slice of Brooklyn runs bus tours of Brooklyn with a focus on two incredible pizzerias
Nashville Pizza Tours runs various tours of Nashville with pizza stops along the way
Naples Pizza Hostel is a bed and breakfast that also hosts fantastic tours of the birthplace of pizza, Naples, Italy!

Pizza Industry 
Pizza Today Magazine is the leading pizza industry trade publication
PMQ's Pizza Magazine publishes monthly articles as well as podcasts and online content
Pizza Marketplace is a web-based pizza industry news site and email newsletter
Pizza Expo is the world's largest pizza industry trade show held in Las Vegas
Pizza Pasta Northeast is a pizza industry trade show held in Atlantic City
Smart Pizza Marketing offers marketing, consulting, and runs both an excellent podcast and daily newsletter with pizza biz info

Extra Cheese
Slice Out Hunger is the pizza industry's hunger relief charity 
Pizza Therapy is Albert Grande's pizza lovers' home base
Pizza Quest is Peter Reinhart's collection of videos, podcasts, and blog posts about his quest for the perfect pizza
Pizza History Book is Peter Regas's blog about his deep archival research into pizza's origins
The 'Za Report follows the adventures of pizza enthusiast Miriam Weiskindd
Son of a Pizza Man offers marketing and graphics for pizzerias, plus a YouTube channel filled with pizza content