Below are a list of some of the best curated lists of tools to assist an internet investigation. Check back for regular updates. If you find a resource worth adding please feel free to link in the comments.
Michael Bazzell Inteltechniques: https://inteltechniques.com/menu.html
Jivio Awesome OSINT (GitHub): https://github.com/jivoi/awesome-osint
Justine Nordine OSINT Framework: http://osintframework.com/
Robin Good: https://contentcuration.zeef.com/robin.good
Paul Myers Research Clinic: http://researchclinic.net/
Dr Neal Krawetz: http://fotoforensics.com/
OSINT Pioneer 