Thanks to for all the quick replies to my question.  Here's the original
question and the two solutions that worked:

I have a bunch of Orthophotos in MrSID format that are in the correct
projection (NC Stateplane) but wrong units (meters instead of feet) so
they don't lay over the rest of my layers.  I've downloaded aerials and
world files before and been given the option to have the world file for
either feet or meters with a single image file...this leads me to
believe that I could simply change the information in my world files to
get the image to display in the correct units.  I tried multiplying
through the meters by 3.2808333 and saving the new file, but the image
displayed in the same place as before.  Can anyone help?  Can I
reproject the images?

1) Use the free image viewer/manipulation program ViewFinder from
Erdas.  This program allows you to change the projection of image files
including MrSID format.  However, you can only save your output as
GeoTIFF or Erdas IMG files so my nice compact 8mb MrSID file became a
huge 130mb GeoTIFF.

2) This option might only apply to MrSID files...but I suspect would
work with any georeferenced image with a world file.  Basically, just
change the information in the world file.  In my case, multiplying the
meters units by 3.28083 to convert to feet.  The catch is that MrSID
files might have some referencing information imbedded in the image
file.  The fix to this is simple.  Open the .SID file with Wordpad and
find where it says "image : : XY_origin"  (use the search command to
sift through all the strange characters).  Once you find it, delete it
along with the characters that follow...up to the next "image" line.
Save the file.  Now you have a modified world file and a modified image
file.

Thanks again

Joel

--
*******************************************
Joel T. Bell
GIS  mapping specialist
North Carolina Coastal Land Trust
*******************************************

"It is of great importance that the general public be given
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