Would this place work? http://earthdata.nasa.gov/ I was able to download a DEM in TXT format, but I'm really not certain it will work and I do not have access to try it. If someone is interested to help to see if this data works, here is the data.
Never mind. The downloaded file contained a URL not related to the data I wanted. Sort of bogus, really.
This looks okay -http://gdex.cr.usgs.gov/gdex/, but I haven't tried the data yet. You need a login.
The best source of DEM data remains the USGS Seamless viewer, which includes high resolution data for the US, as well as medium resolution (best available anyway) for most of the rest of the world: http://seamless.usgs.gov/
To get TG2-compatible data, when you select your data to download, go to "modify request" and change the data download type (typically default of ASCII) to GeoTIFF.
- Oshyan