I would suggest that you have a couple options to assist in the return of the money or the property....
You might consider trying the police again. If the one officer has been helpful, then utilize his services. If he has not, then consider contacting his supervising officer, perhaps the next person up the ladder might be more helpful. As you suggested, you could certainly report this as a theft. Theft is commonly defined as the taking of the property of another with the intent to deprive the person of the use of that property. The actions you have described certainly fit that definition.
You might also consider a civil lawsuit. While theft is normally handled in criminal court, the taking of another person's property can also be handled by way of a civil lawsuit.
While a criminal action could be handled for you without ever hiring an attorney, it would be prudent to retain counsel if you pursue a civil lawsuit. If you are looking for an attorney, you should begin with your state bar association. The Massachusetts State Bar has a website, it is located at www.massbar.org.
I do not know your county of residence but your county bar association likely has a similar site that will be more specific to your location. A quick Google search will locate the appropriate bar association. For example, you might search "barnstable county bar association".
Additionally, Martindale Hubbell is a national organization that rates attorneys across the country. Their website is located at http://www.martindale.com/.
Another nationwide website is located at http://www.avvo.com/. This site lists attorneys by geographic location and area of practice.
Additionally, there is quite likely a legal aid society in your area. A quick internet search and/or phone book search should locate the society closest to you.
Each of these resources will have a wealth of information as to attorneys in your area that handle such cases. I would suggest you check each site out and you will surely find a great number of attorneys that meet your needs. Pick a few to meet with in person so that you can thoroughly explain your situation and then retain the one that you feel can best represent your interests.
Please let me know if anything requires clarification.
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