To format currency, click on Help and type in  "Numeric picture switches"
for instructions and examples.

Hi Lynn,

What you need to do is to test each MERGEFIELD's contents for a value >0,
and add a numeric picture switch to the displayed value, thus:
{IF{MERGEFIELD ItemTypeCost}> 0 "{MERGEFIELD ItemType}[tab]{MERGEFIELD
ItemTypeCost \# $,0.00}[cr]" ""}
where the [tab] and [cr] represent an actual tab and carriage return (or
line-feed), respectively. When doing this, you don't put carriage returns or
line-feeds between the different sets of MERGEFIELDs, except for after the
customer name.

Oh, and how to do this? Select the MERGEFIELDs and press Shift-F9. That will
expose the field coding, which probably looks something like:
{MERGEFIELD ItemType}[tab]{MERGEFIELD ItemTypeCost}[cr]
Select a given set of these fields, tabs and carriage returns/line-feeds and
press Ctrl-F9 to put another field around them, thus:
{ {MERGEFIELD ItemType}[tab]{MERGEFIELD ItemTypeCost}[cr] }
Then put the cursor between the first two field braces (ie '{ {' ) and press
Ctrl-F9 again to insert another field, thus:
{ { } {MERGEFIELD ItemType}[tab]{MERGEFIELD ItemTypeCost}[cr] }
Now simply type the rest of the information in, being careful to replicate
the character spacing here (> 0 ") and here ([cr]" "") exactly.

When you're done, select the whole field and press Shift-F9 to update then
run your mailmerge.

Cheers
PS: You can't simply type the field braces - they must be created via
Ctrl-F9