I travel a lot and am sometimes not with my computer for over a week. Is there an AC adapter available, or what output would be compatible?
Lots of posts here on this; you might want to try using the search box at the upper left.
Basically, a general AC USB adapter will work. Should be 5 volt (more will blow the Clip out); amperage should be fine as the Clip will take what it needs (a low end of 400-500 mA should be fine).
Name brands are available, e,g, Macally, DLO; many no-names are out there as well that will work, but note that there can be quality issues. You may want to check out eBay and Amazon.
Also: note that a cellphone or GPS AC charger that you already have could work as well.