It looks like only police can solve you problem!
however, most of the police may not be able to solve internet crime.
There are special division for the police department where you can complain things like this and it will be an advantage for a country that recognize bitcoin and cryptocurrencies.
FBI can do the job if you're living in America but if not try to search on what particular agency is assigned to receive these type of complains.
And also mate, don't underestimate the bravery and knowledge of police force. I do support their arm for controlling and reducing the crime rate and these such acts will be solved by them.
I would say they do really have the capability to trace transactions but would really be a tough job for them. We do know how transactions happen on this cryptocurrency world which its just new and authorities are just new into solving these kind of cases but i do believe sooner or later they would able to make some ways on resolving crimes which is good and would be helpful and will surely lessen up specially on hyip or ponzi scheme scams since these are the most common investments do involve on making illegal.