I also know for a fact that many companies go to programming conferences to look for people to hire. Attending those conferences is a great way to network. Even better is to present at a conference.
I've also seen a lot of recruiters going through GitHub and contacting people that way lately. People with public source on GH tend to be really passionate devs because they're frequently spending time outside work doing dev.
If not, then can you share some tips on how to concisely include a job applicant's open-source contributions in their resume?