Watch a video or two and get the 1 spin ball for 10 credits... You will probably get 6-10 rounds on them maybe? It's worth it if your just starting... I'm still a rookie about level 36 and they helped me shoot a few 70's and a 68! Thats with stock starter equipment and the lvl 19 spider putter...
10 credits for 1 spin ball much better than the free ball IMO.
Many 1 putts to you my friend