Lead generation can be found in the most unlikely places. If not lead generation, than brand advocates, potential clients, and reviewers of your product.
This quick video gives you an idea using Google Webmaster Tools and the Crawl Errors to see who
We are all exposed to more structured forms of Lead Generation, but don't forget to look in those unlikely places. This is especially helpful for small businesses who want to see who is actually linking to them, and who might care enough to correct the links. If they took the time to link to you before, chances are they will want to correct the links on their site and learn what's new. You may have to try a few contacts - the person who updates the website may be different than the person you want to talk to and hear from. Perhaps not, perhaps you are opening the door to a new type of advocate, one that can affect organic search results and rankings and the one who people don't usually seek for alignment.
Don't forget to ask them what's new with them and their companies.
And remember to LISTEN - REALLY LISTEN to the answers.
Make a list of the pages that link to your broken content in one column, the broken link in the next and the corrected link, if any next to that to make it easy to request they update their posts that link to you. They probably don't want broken content links any more than you do. Add an action column and use this or import it into your CRM.
Worse case, you have your list for your 301 redirects. But, that's another show, another day.