How would I get all that hard work back? Does StackOverflow have a mechanism to recover good stuff that was deleted by some else (like the author of an answer)?
Someone posted an answer to my question which turned out to solve my problem, but he deleted it. I dropped a comment on my question asking him to undelete it in hopes he would see it if he stuck around. Lucky for me, he saw my comment and undeleted his answer.
However the comment @reply notation doesn't actually do anything special when addressing people who deleted an answer to your question. That was just luck on my part.
I think a better idea is to flag your question asking if a mod can reinstate the answer for you. Also leave a comment, though, as people with high reputation who see your comment can then vote to undelete answers if they agree that the answer helps (and a mod hasn't stepped in yet).