I recently went in to a SS office to do some paperwork. I asked about the best way to apply--first, go to
www.USA.gov, follow the links, apply, its a long procedure, make sure everything is filled out correctly.
Second, search their listings daily.
Third, don't be afraid to actually go to the SS office you're interested in and hand your resume to the front desk. If you call they will just say to apply online, but the lady I spoke with told me people do come in all the time with resumes, and oftentimes they are routed to the hiring manager. It helps if you can somehow find the name of the hiring manager, then ask it go to him/her. don't expect to be interviewed on the spot, they're way too busy for that.
But they're also way too busy to wade through all the applications online. If a resume targeted for a position they have is handed to them, they might just read it and be interested in it.
Just go to the front desk, or ask the security guard, to please deliver your package to so-and-so. don't tell them its an application. have it in a nice envelope, sealed, they will probably deliver it just because they don't want to be at fault for not delivering an important communication.
This method could work, remember, they're human, too, some are nicer than others, just keep trying!