*Cracks knuckles* Here we go!
As many have said, online applications are the main way to do things this day and age. I've seen Monster mentioned, which is good; Linkedin is another big name, though that seems to be more geared towards white collar jobs, at least for me. Snagajob is also another excellent one, and they seem to be WAY more active than Monster in terms of emailing you info; every day without fail I'm emailed a short list of places that are hiring.
If you're looking for jobs outside of those sites, I find typing in Company Name Jobs is the easiest way to find that job's application site. For instance "McDonald's Jobs" will usually net you the page that you can get right into the job application process from (if not that, then getting there within a few clicks).
If you're in this for the long haul, one thing that's helped is making an Excel Spreadsheet that has all the info on jobs I've applied for: Name of the job, position, date applied, location, how long before I can re-apply, and so on. I've recently expanded the spreadsheet to include tables for job history, login info (LOTS of places will have you make accounts), and contact info, all right there at my fingertips for quick referencing.
Also. Be persistent. Don't forget that one. Good luck!