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:

 

Also see:

 

 

OSINT Attack Surface Diagram for Usernames

Username OSINT by @sinwindie

 

 

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