Why isn't my iPod Touch (4G) showing up in iTunes or in My Computer??

Well my iPod Touch (4th Generation) was working great until yesterday. I was trying to update the software (iOS 4.3.3) and after 4 HOURS it tells me that it cannot install the update and now my iPod won't show up in iTunes or My Computer and it is showing the screen it usually does before you set it up. I checked the Device Manager...(Windows XP) and it's showing up as "Apple Mobile Device." I tried searching for hardware changes but nothing is working...I mean I am constantly fixing the iPods of other people but this time I can't even fix mine...oh and as a side note I did restart the computer and then after a while turned it off...I tried restarting my iPod too but to no avail. Please help!!!

Thanks!!=)