My itouch wont connect to itunes or mediamonkey!? ?

the itouch i got was the displayed one at the apple store. it was sold out and i had no other choice but to choose to buy that one. its got cool games on it already. but i want my songs on my computer to be synced onto my itouch. at first, i was trying to register with itunes but i think someone already did at the store when he put this one on display. i've tried to plug in and plug out a million times and either my itunes or mediamonkey would detect the device. geez. i also want to delete the ugly pictures and songs they put onto my itouch. please help!