Its a Good Idea Shane, however I will only recommend you "not to keep it free" because it takes a lot of work, time & energy to compile such things.
Even if you can monetize big through Affiliate Links or Banners in your Email, $20 seems fine, if you like you can start with $10 for first month, just an idea.
Moreover, my advice would be not to make commitment for daily mails, it may become very hard for you to keep that commitment in the long run. If you are working that hard to find such a large number of names, then 15 Mails per month seems fine with $10-20 subscription price, with a commitment of at least 3 mails weekly to your subscribers, imo.
Regards//Daneyal