Hi,
When you bought your MacBook, it came with an operating system, Snow Leopard, pre-installed.
It also came with some applications, including iPhoto, iMovie and Garageband, pre-installed.
But the iLife applications aren't part of Snow Leopard, or of Lion.
They're separate applications, and Apple gives them to you for free when you buy a new Mac.
If you launch iPhoto, then go to the iPhoto menu and choose "About iPhoto", you can find out what version of iPhoto you're running. You can also check for software updates, and if they are available you will be able to download them.
Your MacBook is very new, and I would be almost certain that the version of iPhoto you're running is the same as the version in the AppleStore.
But if Apple upgraded iLife to a new version (possibly iLife 12) you would have to pay for that if you wanted it.
And if Apple upgraded Lion to a new version (possibly Ocelot 😉) you would have to pay for that separately. It would not include the iLife applications.