After many years on the Internet (since the 1980s - pre-web !) and many more years since it has proven impossible to keep up-to-date, this catalogue has been officially retired. There are now numerous sources of information about digital elevation data on the web, together with international metadata repositories such as the GeoSpatial One Stop Shop and FGDC in the USA, GIgateway in the UK and a number of INSPIRE-related spatial metadata initiatives across Europe. The EROS Data Center is a good starting point for global data.
Good luck!
Bruce M. Gittings,
University of Edinburgh.