Personally, I believe that you should:
1. Send him a hand written note thanking him for giving you permission to hunt his land;
2. Ask him when he'll be in the area because you'd really like to meet him;
3. Offer your services to watch his property any time he is away to include non-hunting periods;
4. When you do meet him, a sincere and hearty hand shake for giving you this priviledge; and
5. Then put him on your Christmas, Easter, Thanksgiving, and every other list to send him a card.