Make a small subset of your table, and format the column for $999,999.99. Click the little red triangle in the upper left corner and select Copy Table Script. Paste the script into a script window and you'll see something like this:
New Table( "Untitled 2", Add Rows( 5 ),
New Column( "PricePaid", Numeric, Continuous,
Format( Currency( "USD" ), 17, 2 ),
Set Values( [12345678, 43256443, 345353, 5545352, 53245345] )
)
);
The relevant portion of the table script is on line 3. You can pull this out like so:
dt = current data table();
column(dt, "PricePaid") << Format( Currency( "USD" ), 17, 2 );