Getting an enrollment in a golf academy, whether it's for a few days or a few weeks, is a great idea. He'll like the thought behind the gift and you'll appreciate a little less complaining about his golf as his game improves.
Golf balls are easy to wrap and you know they'll get used. If you're not sure what brand he prefers, sneak a peek into his golf bag and see what's in there or ask one of his golfing buddies for suggestions.
Automatic Return Putting Cup
They've been around for years, but they remain a popular "toy" for home or office. Throw in three practice balls, maybe personalized models, just for fun.
Plenty of golf carts are equipped with GPS technology, which can tell you how far you are from the hole, but a hand-held model such as the SkyCaddie can come in handy too. It's also lightweight and small enough to fit inside his golf bag.
Golf Store Gift Certificate
It's not quite as personal, but instead of trying to pick out a new putter or a new bag, give him a gift card and send him on his way to browse.
If a golf tournament is coming to your area, or if you have the budget to send him away for a long weekend, think about buying tickets to a PGA or Champions Tour event. Online ticket brokers and the tournament websites have ticket purchase information. Every golfer enjoys seeing the best tour players live, and this could be an especially memorable present for the golfer in your life.