You have to dig for them one by one and it is a lot of work. Many businesses have local tenant rep brokers they have used for years to scrub sites first to see if they have potential. Corporate execs for name brands do not have time to look at junk sites all day. They only want to be bothered if the site is incredible or their tenant broker has said it has potential and go to the next step.
@Alberto Nunez my partner and I are testing out realtytrac. We had a contract on a property and they barely seemed responsive. Looking to see what we can do on our own before revisiting options. At the very least, we're trying to identify the correct broker connected to the target tenants we're interested in. What kind of tenant for the property? We have some contacts with existing tenants in free standing retail.