You can drop off your absentee ballot from 2pm to 4pm on Wednesday the 13th.
Yep, that's tomorrow!
The Embassy is at 4300 Av. Colombia, Palermo.
If you just want to drop off your ballot (in postage paid envelopes) without going through security go to window 1 (street entrance), from 2:30 to 4:30 (Mon-Fri, excluding Oct 11 and 27).
Happy Voting Day America!
"We will accept ballots up to and including November 2, 2010 (REMEMBER – some states will accept ballots postmarked by November 2, while others have an earlier deadline--check your state’s requirements on www.fvap.gov.) For additional details, visit the Federal Voting Assistance Program or the Overseas Vote Foundation. The Embassy's Voting Assistance Officer will also be happy to answer your questions about absentee voting; simply send us your question at VoteBuenosAires@state.gov. "