I think part of the problem is that companies are well aware how difficult it is to get decent dev talent these days, and are thus careful to retain their staff, making your job a lot more dificult.

I think we have also become jaded to traditional recruitment tactics. Additionally, I think it is fair to say that amongst the things that developers with industry experience have learned is that the average recruiter is, sorry to say, useless*.

I think it is this, along with social networking sites like LinkedIn.com that are making your job difficult.

Suggestions? Hire recruiters that have some sort of dev background themselves so that they understand the environment. Use social networking sites to your advantage. Be honest and open. Look after the people on your books because they will come back, and they will bring their friends.

* There are some notable exceptions, but they are in the extreme minority.