US student interning at a startup abroad -- where to look?

I'm a CS student (will be PhD candidate starting August 2014) in the US and really want to experience a different culture before graduating by interning abroad (at a startup!).

Where can I find information on this? Trying to search for this on my own only brings up results like "Unpaid internships abroad"

Also, is this unrealistic? Will sponsoring me for a summer be too much effort for companies? I've met other interns in the US from out of the country.