Probably the carom section of AZB would be the place to ask whether the USBA rules differ from those of the world body - the Union Mondiale de Billard (UMB). Bob Jewett or somebody of similar authority would certainly know. I do believe, however, that they are the same.
The French-to-English translation of the official UMB () rules is here:
http://www.umb.org/Rules/Carom_Rules.pdf. It's a decent translation, but a bit literal in places. These rules cover straight rail, both baulk line games and one-cushion as well as three-cushion. They also cover table dimensions, etc, which I don't believe are in the USBA version.