Well, it looks like we accepted all offers of assistance, even Venezuela's. Except for Cuba, which the US said it is waiting for an official extension of aid offered through proper channels. Further, the State Dept. insists:

"A State Department official said there were "absolutely no political
considerations" being taken into account, and that the U.S. government "is
not turning anything down."

http://www.cnn.com/2005/US/09/06/int...ows/index.html

For a complete list of who gave what: http://www.cnn.com/2005/US/09/06/int...id/index.html/