Craigslist, mostly. I don't even have a LinkedIn. It's worked fine for me so far as a software developer, and gotten about half of my jobs. The others were found through friends. Sometimes you can send your resume directly to the CEO or CTO of startups, skipping any go-betweens; I got at least one interview that way.
If you're in a blue collar field, probably wouldn't hurt to just randomly walk up to small businesses and inquire. Social skills are rare these days so people tend to respond positively to someone who is willing be social.