Until it's been a couple of months at least, you can't really assume that the companies you are signed up with have no shops in your area. Since there is so much competition, a lot of shops go really, really fast, so it's not often that you will sign up with a company and log in to find a huge Job Board with jobs just sitting there waiting for you. Also, there tend to be a lot fewer jobs near the end of the year and during the holiday season. A lot of companies don't want to be mystery shopped during such a busy period so I've noticed things are really slow. I would use this slow time to sign up with a lot more companies.
Keep in mind that the people who know about jobs specifically in your location are people who live near your location and are doing those shops. Since they are your competition, they are unlikely to share a list with you.