Software

Processing
Flex
AVR Libc

Hardware

Arduino
Seeed Studio
Modern Device
Make Controller Kit
Liquidware
Beagle Board
Gumstix
Illuminato X Machina
XBee
Bug Labs

Buy Parts

SparkFun
Jameco
DigiKey
Mouser
All Electronics
BG Micro
Ax-Man Surplus (my favorite local place)

Learn to Build Things

Make Online
Instructables
AVR Freaks
Hack A Day
Chiphacker

Connect with Actual Humans

Ignite
Maker Faire
Dorkbot
NYC Resistor
BarCamp
Twin Cities Maker

Get Inspired

TED
Design and the Elastic Mind