Ajax message box for customers

I'm looking for a coder who can make the following: Ajax message box in our contact page, controlled by admin. If there is a message in admin, the box is displayed in our contact page, if no message, then no box. It doesnt need to be ajax, it can be done php as long as the function is the same. Need someone to start just now and complete within a could of hours max Small budget pls, easy small job