I have an inventory spreadsheet, the first worksheet keeps a count of what we
have and what has been sent out. What I need to do is count the number of
items of a specific product that has been sent out, based on the date it was
sent. Furthermore, because new information is regularly added, I need to
count from the entire range of column.

Example:

Column A = Date sent, Column B = Product Model

A B
7/12/2007 T60
7/12/2007 T60
7/20/2007 X60
7/20/2007 T60
Blank T60
Blank X60
Blank T60
7/13/2007 X60

From this example I need to count on a different sheet the number of T60's
that have been sent without counting the X60's or the models that have not
been sent out (i.e. Blank).