I am a professional Data Research Analyst with a reputed Recruitment firm in India. I have previously worked with Fortune 500 companies and have mined over 15000 HR email addresses.
I can proficiently employ the below techniques to research email addresses for you.
1. Boolean Search on LinkedIn, LinkedIn Sales Navigator. I also have an access to a premium LinkedIn Account.
2. X-Ray Search on Google.
3. Stack Overflow Research and GitHub Research for Tech profiles.