hello i have an ipod touch i bought a couple of years back and i can't remember which gen it is. how do i find this out? I need to find out the gen of the ipod touch so i can buy a replacement battery as my ipod is no longer holding a charge for any length of time. Any advice on what battery to buy? from where? and is it easy enogh to fit a battery into an ipod touch? thanks for any info.