After playing through 15 holes of the last course in World mode, make sure to save it. You must be winning, of course. Then after you have finished in first place and waited through the credits and received your new ball, club and player. Simply reload the save game and play the last three holes (still staying in first place) and get an all new ball club and player.
All the clubs and balls can be unlocked by successfully completing the world tour on difficulty level one (in options). You can also unlock only three of the characters in the level. For each increase in level, you have the ability to unlock two more characters. (i.e. by successfully completing world tour with the difficulty set at level four, you can unlock a total of nine characters.
Highlight the character you want to play with.You can either hold the L-trigger button, the R-trigger button,or hold both trigger buttons and select your character.
You will have a different costume.