Best thing you can do is make a report with you local police station, and talk with an attorney. You can also report the crimes to the FBI (IC3) -
https://www.ic3.gov/faq/default.aspx if your attorney recommends it and the value lost is very large.
You should also take the individual to court since multiple crimes have possibly occurred (blackmail, possibly extortion, using false pretenses in gaining work, fraud by not completing work, Larceny, possession of stolen goods, theft and many more criminal offenses.) Depending on the value of the work and hardware stolen it may become a large number of large felony offenses.
Sounds like all of these were conducted online, with no face to face local meetups? When your work involves hardware it is normally recommended to only deal with people face to face and use escro for payments. Do you still have the signed contracts, if so keep it along with any other electronic or physical communications you may had with the individual.
Did the person give you anything your able to have your attorney get a warrant for information on (email address, online username for a service, etc.) to gather their real name and location?
