Shawn, if it were easy, it would have been done already. ;-)
I think embedded in Kelly's suggestion is some level of automation.
"Manual work" can almost always be automated for very, very little. As an example, I just had someone build a tool that scraped company names from a few thousand pages, guessed at their domains, looked up specific roles on LinkedIn and then generated/validated emails for them. Certainly not perfect but 4 hours to write a spec, and just a few hundred dollars to implement.
More often than not, the data is out there.