I think there's definitely a market for this type of tool if you target it correctly. I'm only a casual golfer, but my dad's a golfing nut. He plays everyday with likeminded golf nut friends, and they all track and talk about their stats to varying degrees. They also watch golf on TV and play fantasy golf leagues. I could see my dad and his friends getting utterly obsessive about a tool like this if it was done right. I could also see them paying for it if they liked it. Golfers tend to be pretty well off on average. I don't think they're likely to be very price conscious about a That said, I think you need to work on your presentation and design. It doesn't inspire much excitement. Instead of listing features and talking about the app, I would focus more on capturing the user's imagination. Don't tell them what the app does. Tell them why they should care. Communicate more on an emotional level. That's where the decision to use/buy will be made.
The screenshots also look a bit dull. I know it's just an analytics dashboard, but I think a shiny interface is going to be important. You don't want someone's subconscious visual impression to be 'glorified excel spreadsheet', you want it to be 'futuristic intelligent stat crunching engine that magically improves your score'. Regardless of what the app does, the way it looks will deeply influence how powerful it is perceived to be. Imagine a golfing scene from some sci-fi movie set 100 years in the future. What's the interface on their super advanced tablet going to look like? That's what to aim for.
Last piece of advice: I would look at the ads in golf magazines or on TV for guidance on design and language. Selling equipment, gadgets, and media to golf nuts is a huge industry. The companies that have been around for awhile are experts at marketing to this demographic. The same techniques that convince someone to buy a new $500 driver or instructional dvds or some useless magnetic bracelet could definitely convince them to buy software that provides useful statistics if you present it right.