Excel email alerts

I’ve created a training programme in Excel 2003, with a sheet for each team member detailing past/current/future training courses attended. Some of the courses are time critical and must be renewed before they expire to maintain validity. I’ve created a cell for each course indicating whether they are current/need booking/overdue however I’d like to go further and have the cell email me an alert when courses get within 60 days of renewal. The 60 day bit is of course easy, but does anyone know how I can create the email alert?