Here are some useful links. Enjoy!
Real-time PCR Tutorial
Real-time PCR Protocol
Real Time PCR Primer and Probe Database
Real Time PCR Primer Sets
IDT Primer Quest
Invitrogen OligoPerfect Designer
Invitrogen Block-it RNAi Designer
Qiagen siRNA Design Tool
Gene-quantification
PCRLinks.Com
CodeHop Primer Design