Hey! Question here!
Thinking about buying e-mail lis from https://www.emaildatapro.com and send about 100K e-mails
What is the best tool for that kind of stuff? Beyond mailchimp?
You can look for email service providers (ESP) such as Mailjet / Sendgrid
But that is not a good idea. You are likely to loose money buying a list, and immediately get banned for spamming.
All these list that you usually find for sale are pure spam lists, collected by some scrapping tools or acquired via hacking or other malicious means... sending anything to these emails is pure spamming. I'm not saying it can't make $$$ or that nobody is doing it, you just need to understand what you are planning to do.
If you decide to use any service like mailchimp for this, you will get banned very quickly. People who are spamming are runnign their own mailservers on "bullet proof" servers located in Russia or other country that's not very willing to comply with the laws of other countries. Quite a robust system is required to send millions of emails and it's not cheap at all.
Also keep in mind that a large part of advertisers won't take spam email clicks to their offers, most legit businesses want to stay away from it.