Where can I find freelance sysadmins and developers to assist me?

I am a sysadmin and developer, but I am starting to get busy and need some help from time to time. I want to hire someone as a freelancer to assist me with my projects once in a while and also who can explain a few things I don't fully understand. I need a few shell scripts written for automation (Linux), some help setting up and configuring some software, and also just need help with a few other little odd job things here and there as they come up. I need someone who can do development and someone who can do sysadmin (CentOS / RHEL). I would be ok hiring one person who can do both, or multiple people, but I can't seem to find a good resource to do so.<p>Ideally I'd like someone affordable, competent, and somewhat available.<p>Does anyone know of a good place to find such people? Or have a referral?