new scripting question

Hi,

Can you help be figure out how to send an e-mail to someone once a drop down box has been updated. The selection from the drop down box is a employee whose e-mail is on file in another form. I can't figure out how to get the drop down box to e-mail them when it is changed. please refer to my form here...

http://creator.zoho.com/rgranholm/the-california-pet-sitters-crm/view/5/

rgranholm