Stackoverflow doesn't offer search with date filters other than sorting by newest.
Are there sites which use SO's data files and have advanced search filters using dates?
old question, but there is a revolutionary change in search with date filters. You can search by Absolute dates or Relative dates
Examples: Relative dates using d(day) , m(month), y(year)
Examples: Absolute dates
created:2012-04..2012-05 searches posts created between April 1, 2012 and May 31, 2012.
for more details: How do I search?