Simple php if then else include file

Hi, I need a very simple bit of programming done. I am using a form at the bottom of several pages and there is an $email variable that is a hidden field. This $email should be substituted for an actual email address but because I do not have any type of email database, I would like to include a php file that will select the correct email address based on another variable $propertyname. In other words : if $propertyname is equal to Prop1 then $email will equal cdatcddotcom else if . . . . Hope that makes sense to you php programmers out there. I'm sure it could be done for less than $30 so get bidding everyone.