This is not a panacea, but free SMS validation of wallet holders can be done here:

http://www.antifraud.com

It sends an SMS message to a wallet holder and collects their response, geolocation, organization and has a community database of fraudulent wallet holders.

It should only be used to make sure the wallet holder has a traceable phone and where they are matches your expectation (like, the guy supposedly from Indiana is actually in Belarus).

This will not stop fraud, but it will make it harder.