Ask the person directly
Check their LinkedIn profile
Look at their social media bios and posts
Search their name in search engines
Review public professional directories
Check company websites and staff pages
Search alumni or association directories
Use mutual contacts to ask
Look at email signatures or business cards
Search public records where available
Check conference speaker or event bios
Search news articles or press releases
Look up their online portfolio or personal website
Search licensing or certification databases
Use people-search websites where legal and appropriate