enjay,
I am assuming here that you have already imported the days form into excel format and want to just quickly highlight the runners.
I am also assuming that you have imported all meetings onto a single sheet for the day.

Assuming much, here is my advice...

Have a format where you sort the data into columns, e.g. date track runner etc.
Then select the row with the headings and select Data from the main toolbar, then filter and select autofilter.
You will then be given a drop down menu on each heading where you can select the horse or track etc.

HTH.