HI, I was trying to load a 1:240000 10 meter DEM from the Geo Community web site
http://data.geocomm.com/catalog/index.The data is free you just need to sign up for an account.
Here is a sample of the text portion that comes with the file
ITEM_TYPE: SDTS DEM - 7.5X7.5 GRID
CELL_NAME: Anthracite Range
STATE: CO
MRC_CODE: 38107-G2
BEST_AVAILABLE: T
SALEABLE: T
DATA_LEVEL: 2
X_RESOLUTION: 10
Y_RESOLUTION: 10
XY_UNITS: Meter
Z_RESOLUTION: .100
Z_UNITS: Meter
ORIG_LOAD_DATE: 05-FEB-03
CREATE_DATE: 05-FEB-03
PUBLICATION_DATE: 06-FEB-03
SOURCE_DATE: 1958
INSP_REV_DATE: 2002
INSP_REV_NAME: Inspection
HORIZONTAL_DATUM: North American Datum of 1927
PROJECTION: Transverse Mercator
ZONE: 13
VERTICAL_DATUM: NGVD 1929
DIGITAL_FORMAT_SPEC: DEM SDTS (Part 5: Raster Profile and Extensions (RPE))
STANDARDS_NAME: Standards for Digital Elevation Models 01/98 Specifications
PROCESS_STEP: DLG/Hypsography LINETRACE, LT4X Complex Linear
MIN_ELEVATION: 2413
MAX_ELEVATION: 3789
SUSPECT_VOID: 0
PERCENT_VOID: 0
LARGE_CONTOUR_INT:
SMALL_CONTOUR_INT: 40
CONTOUR_UNITS: Foot
RMSE: 0
SAMPLE_SIZE: 30
NORTH_LATITUDE: 38.875000
SOUTH_LATITUDE: 38.750000
WEST_LONGITUDE: -107.250000
EAST_LONGITUDE: -107.125000
The extension of the file format is .DDF