piztaker: I suppose I'll just have to pay again.
No, that's not necessary. The club is in your inventory, it just needs to be equipped.
Please click the PLAY NOW button and load the game as if you were going to play. Once it loads go to the My Settings tab and choose My Equipment.
You should now see a screen like the one below:
Click the Green arrow on the left to scroll through your club options. You should see a Beginner Driver (the one currently equipped), a Starter Driver and your new Tour Starter driver. Scroll to your new driver and drag it (click & hold) to the first optional club slot on the far left. After you've done that click SAVE CHANGES.
If you do not see a third driver, please follow this link for instructions on how to clear your flash & browser caches. Once you performed both steps and have cleared both caches try to equip your new driver again.