Consider checking out the Email Purmutator to see what combinations of firstname.lastname you may haven't thought of yet.

Good article on OSINT for Usernames:

https://cylab.be/blog/121/osint-simple-tips-4-usernames

Username OSINT Apps:

• Spiderfoot
• Maltego
• sherlock
• profil3r
• linkedin2username

Also see:

• OSINT for Social Media
• OSINT for Email Addresses
• OSINT for Phone Numbers

OSINT Attack Surface Diagram for Usernames

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