For an iPhone I would try the following:
If iPhone doesn't appear in iTunes or you can't sync iPhone
1. The iPhone battery might need to be recharged. For information about charging iPhone, see "Charging the Battery" in the iPhone User's Guide.
2. If that doesn't work, disconnect other USB devices from your computer and connect iPhone to a different USB 2.0 port on your computer (not on your keyboard).
3.If that doesn't work, turn iPhone off and turn it on again. Press and hold the Sleep/Wake button on top of iPhone for a few seconds until a red slider appears, and then slide the slider. Then press and hold the Sleep/Wake button until the Apple logo appears.
Note: If you enter the SIM PIN incorrectly three times, you may need to contact your carrier for a Personal Unlocking Key (PUK) to enable your SIM card again.
4.If that doesn't work, restart your computer and reconnect iPhone to your computer.
5.If that doesn't work, download and install (or reinstall) the latest version of iTunes.
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You could also try using a different USB iphone/ipod cable to connect your device to your computer.
If you already tried all these suggestions from Apple, then you might just want to take your device to the nearest Apple store by you (if you have one by you) and have them check out your device to see if they can't get it up and running on their computers.