Can you get an IT job without using an agency?

My boyfriend has been looking for an IT job for months, and he keeps applying for jobs on websites and sending his resume to agencies in Boston, Indianapolis, and Chicago. They call him and tell him that they like his resume, but nothing happens after that. I asked him why he doesn’t just apply directly to the company in need of an IT person, but he says that he has to apply through an agency. Is this true? I mean they are calling about jobs that are for only 3-12 months!