i am afraid i think it has been deleted, this ac was bought as a present and not liked so i purchased it, is there any way i can retrieve iPhotos? it was one of the main reasons i bought the mac
So you used Spotlight to search for "iPhoto" and you looked in Applications in Finder? If you find it in Applications, you can drag the icon to the dock (row of App icons on the bottom of your screen) and it will create a "shortcut" or "alias" as it is called in Mac OS.
Since you purchased used, it is either running Snow Leopard, which means it should come with install discs that you can use to reinstall iPhoto if it is in fact missing from your MBA.
OR
If you have Lion or Mountain Lion as the OS, it is likely set up in the old user's name and Apple ID (the ID you use in iTunes and app store). If that's the case, you have to start over by purchasing Snow Leopard disc from Apple.com and then going into the Mac App Store (an app on the Mac) and purchasing ML. That will give you the most recent everything.
Let us know what OS you're running and if you're able to find iPhoto in Finder/Applications.