JdhMac: So there is a way to earn credits without paying, right?
You can win credits, in symbolic amounts for most players, by participating in tournaments. The payout in the new "ready-go" tournaments is higher, but the entry fee is $1.00. You also get symbolic amounts of credits for advancing to the Amateur/Pro/Master tier. Theoretically, you could also wager your first free 100 credits to challenge others for match-play games, and go on winning from there until you have enough credits to buy decent clubs, but that's a rather unlikely scenario for a beginning player.
JdhMac: By the way, so a full practice round will "count" towards something [...]?
No, it will count towards nothing. You need to play a ranked round (9 holes is enough) if you wish to lower your average score.