Aerial photography
From Wildsong
How to get the camera up there
Kites
Small aircraft
Lighter than air
Image collection
Georeferencing
GPS-Photo is a product from "Geospatial Experts" Looks like what you do is collect GPS data and then take pictures with a standard digital camera. You have to make sure the clock is set correctly in the camera. Then it builds a shapefile to correlate the GPS dataset with the images. They also sell cameras and gps receivers to create a complete bundle.
Links
Article about the seal project that Brady worked on: http://www.esri.com/news/arcuser/0205/seals.html