macbook pro didnt come with CD

Since the OS X Lion release, Apple doesn't provide any discs with Macs. If you want to reinstall OS X, you have to use Recovery HD or Internet Recovery > http://support.apple.com/kb/HT4718

Apart from that, now iPhoto, iMovie and GarageBand are installed from the App Store, so you just have to uninstall GarageBand, open App Store > Purchases, and download and install GarageBand for free. Probably this won't solve the problem, but this is the way to reinstall an iLife application

laladk wrote:

i have the OS X 10.8.3 version. Was it supposed to come with a CD?

Nope. No optical discs have been included with new Macs for over a year and a half. They are no longer necessary.

You can reinstall the version of OS X that shipped with your Mac as often as you want, even if you replace its hard disk with a completely empty one. Whatever you purchased from the App Store, including GarageBand, can also be reinstalled as often as you want, and on as many Macs as you own.

To uninstall anything you purchased from the App Store, drag its icon from the Applications folder (not the Dock) to the Trash.

To reinstall anything you purchased from the App Store, click the Purchases icon in the App Store, and download it.

laladk wrote:

just an update: i went to purchases this time n it said 'install' so i did, but it didnt mention having to pay, so i assume the only reason it said that before was because i searched for GB and went to the app page etc..?

Yes. The "Purchases" tab is what you need to use.