You might want to get ahold of the 1999 version of Fowler's Modern English Usage (Oxford), which bears only a nebulous relationship to the original Fowler's but which has much info. on Brit vs. Yank English. It's edited by one Robert Allen; his grasp of the subtleties of North American English is a little slippery, but I think it's safe to assume that he would not have gotten the job if he didn't have a pretty good handle on standard British English. Also, he's not overly impressed with the Victorian grammarians (which is to say, he's not one of those who believe that all the grammar they were taught in school is necessarily correct. Note: that's those who believe, not those who believes!).