create email if greater than todays date

Hi

Im am entry level excel so in short "clueless", and looking for help.

I am trying to create a macro to tell admin dept when our employees training certificates are due for renewal.

i.e

Column A "Employee Name"
Column B "Date Trained"
Column C "Training Renewal Date"

I have a cell in Column D thats is function "TODAY" for todays date

And the admin girls email address in the next cell below

I would like to write / learn to write a code to send an email to admin girl when "Training Renewal Date" is greater than todays date,

so that she can arrange training for the employee,

any help would be appreciated, even parts of the code to get me started would help any ideas welcome

thanks

Kev - London