Yes, as long as the quota is not filled yet. The applications can be submitted starting of April 2011 (I'm assuming "for 2011" means for "for 2012" which starts in October 2011 per USCIS), and until the quota is filled. For 2011 (that started on October 2010) the visas were available until January 2011.
If you mean FY 2011 that ends on September 2011, then no, once the FY ended the visas are no longer available. But the visas for FY2012 will probably still be available, so it shouldn't be a problem.