Search tools:

www.searchtempest.com   Multi-city Craigslist, eBay search

www.adhuntr.com   Multi-city Craigslist search

http://archive.org  The Internet Archive (aka Wayback Machine)

Training:

LEOTTA (Law Enforcement Officer Technology Training Associates)

Open Source Intel (OSINT) Resources:

http://www.siuhelp.com/ (SIU Help)

http://inteltechniques.com/links.html