Premiumbeat.com provides royalty free music and, apparently, After Effects tutorials. They just posted a tutorial and source files by what sounds like Dave Scotland from CG Swot, After Effects Quicktip: How to Create Realistic Camera Shake.
Other tutorials and options on the subject were discussed recently in Realistic Camera Movement using hand held track. Here's the Premiumbeat tutorial:
Creating a Realistic Camera Shake with After Effects from Premiumbeat on Vimeo.