Ask HN: Hiring contractors for side projects

I'm a freelancer and I have a number of paid projects and unpaid side projects going on at the moment with various people and a few more coming up. I've always been able to manage but now I feel like I'm getting in over my head with the workload. I could of course say no to some of these but a lot of them I really want to be a part of. Have any of you had luck hiring other freelancers to help you with various projects and freelance gigs? If so where did you look and find people?