Maybe. For general programming questions like how to loop two things at the same time or combining two lists into a dict, yeah. For particular open source project if you are lucky yeah you can get help from IRC (or fall back down to reading source code). But infrastructure, scaling, security, these are very specialized areas. You can get a general idea from stackoverflow or security exchange but implementation wise SO is not a good place to find inspiration.

In the past when I had to deal with puppet/chef I constantly had problems that the mailing list just couldn't help and the only way I could get help was to bring someone in and had them debug in real time with me.