Steve Fossett was flying a Bellanca Super Decathlon. It is blue with white starbursts and orange trim. A good photo of a Super Decathlon (in red instead of blue) can be seen below and a link to a page with pictures of the actual airplane can be seen here.
Reports originally said that he went missing while scouting locations for a land-speed record attempt. Since then we have learned that he had already selected a site and may have been sightseeing. RADAR had tracked him in a number of locations and the search area is based on his flight pattern.
There are a number of Search and Rescue aircraft in the area. The Civil Air Patrol alone had over 20 between the Nevada and California Wings. The CAP usually flies Cessna 182's, 172's, 206's and has used at least one Gippsland GA-8 Airvan. Most all of the aircraft used by the CAP will have a paint scheme similar to the one on their home page. And remember, just because you measure a wingspan of 29 feet and the C-182 has a wingspan of 38 feet doesn't mean that it's not a C-182 in a turn while performing a search.
The Hiltons, CHP, Air National Guard, and county sheriffs also have their own aircraft out on the search. Many of them are helicopters or larger aircraft, but they will be seen as well.
And, of course, make sure you're looking at the KML supplied by Amazon instead of the old imagery in the default loading of Google Earth.
The terrain out there is rough and large and very difficult to search. Although I definitely wish the new imagery was of higher resolution this can certainly help in the search effort. But everyone must definitely submit coordinates of possible targets through the Amazon Mechanical Turk website.