What is the best way you've found to recruit staff, apart from going through an agency?

Do you:
advertise in the local newspaper;
advertise on a website somewhere;
look at Monster or other related sites;
ask your employees if they know someone;
chat to your friends;
put an ad in your office window?

And then what are the methods you use for sifting through the chancers to find that one person you want to invest time and training in to keep your business running efficiently?