United States v. Rodriguez, 453 F.3d 458 (7th Cir. Jul. 6, 2006) (for illegal re-entry purposes, a noncitizen if "found" wherever s/he is physically when arrested by federal authorities, not where s/he is first identified as illegally present by state authorities).
http://caselaw.lp.findlaw.com/data2/circs/7th/054786p.pdf