http://rainbow.ldgo.columbia.edu/datacatalog.html
The Lamont-Doherty Earth Observatory Climate Group's Data Library is a data catalog that presents climate information on oceans, atmospheres, forecasts, and topographies. The data catalog page contains information on the data sets, its subsets, and basic design. There is a section that has specific examples with step-by-step instructions on how to use the data catalog. There are links to climate observation groups and organizations.