I find the best way is kijiji. in my industry (Landscape Construction) there is a large turn over of workers. Kijiji allows You to be in touch with a prospective employee the same day, and they can start tomorrow. Since it is usually unskilled labour, I usually hire one or two more then I need because not all will show up in the morning.

Kijiji ads generate alot of response so it is possible to select from a large pool of potential candidate. Try an employee for a day or two to see how they work out. if they dont, there are alot more to choose from.