Back when I needed a job I showed up on a construction site, asked politely, and they put me right straight into operating a crane. Just get out there, pound the pavement, shake some hands. You'll be hired in no time.
People get confused on what a construction site constitutes in comparison to a 19 year old subcontractor dripping paint on a window while his retired uncle yells outdated racial slurs at him.
As a guy who also works on construction sites, if you're looking for site labourers, there's a good chance they'd hire someone who walks in off the street.
No it would not as most construction is done either by unionized workers and/or skilled workers. Most construction jobs require a background in construction.