I builder has had our house tied up in an agreement to purchace and back out of the deal one week before closing. Can I put a lien on other properties he owns

Involuntary liens such as that would have to be provided for by statute. I expect that there is no such statute, although for example there is one for construction liens (http://www.e-laws.gov.on.ca/html/statutes/english/elaws_statutes_90c30_e.htm#BK16) (what we call a "mechanic's lien". The thing you would have to do is file suit to enforce the contract and file a lis pendens (http://www.duhaime.org/LegalDictionary/C/CertificateofPendingLitigation.aspx) at the same time you file the suit.