Get the mailing list of everyone who ever hunted his property , call and mail them about what you are doing on the property. Second think about offering a discount on any new hunters they bring in to the place. maybe 5% if they bring someone.
Offer anothe % if they book early for 2009.

Start a email farm letter of what you are doing and seeing on the property, pictures. News of bigguns killed etc. You have ot get in theor heads that this where they really enjoyed a hunt, had no worries, good food good comraderie. An email letter costs nada to send. Get the address when you call them.

Good Lud luck