Appropriate gifts include tshirts, DVDs, computer or board games, snack food (junk food or gourmet, depending on his interests), sports equipment, and books. Just follow his interests!
I gave my dad things that related to his interests, like little car tools or other gadgets. More than anything he appreciated when I gave of myself. I'd make a dvd of his old family photos or give him some promise notes for time we could spend together doing things he enjoyed. Your dad probably just wants you!
Give dad a year long subscription to a magazine that interests him. It is actually like giving him twelve gifts in one! He will enjoy finding the next edition in the mail each month.
