The fastest way to accomplish this is probably to use Fiverr.com and hire someone to scrape the email addresses and send them to you in a spreadsheet. Or post an ad on Craigslist with a description of what you want and you will get a ton of responses. On Fiverr perform a search for "scrape emails from a website" and you shouldn't pay more than $5-$10 for the work. For DIY, you can use something like Import.io or Parsehub. The general term for this type of task is "website scraping." From a business perspective, I think it's better to pay someone else to do it because it costs nothing and will be faster than doing it yourself. Lots of websites block web scraping these days but people who sell scraping as a service will know how to get around that type of barrier.