How To Sync My iPad To A New MacBook Pro

I just got my new MacBook Pro, and i'm transefing all my applications for iPad and iPhone, music and my photos to my new computer using a Seagate Hard Drive. Anyway, i connected my iDevices to my computer and i do not know how to make this computer be the Mac that transfes everything instead of the old one. When i go to my iPad settings, under general, i go to Wi-Fi Sync and it says i can sync it when 'GABE' is available (that is my old computer). I want it to be my new one and be able to sync with no problems and without loosing my imformation from my iPad and iPhone apps. (For example, i don't wanna loose Pages documents, Garageband songs and FL Music Studio files)

Please help, if you have any questions into what i need please ask, this is a hard question to explain! Thank you so much.