Recently a new site introduced and open to public beta called "Online SignOff ". The Concept is new and interesting. This site will help you to manage, prepare, find and track your contracts, TAC and legal documents. You will be able to create documents, securely e-mail your clients and track the documents when and how they have been read. Additionally the status (accepted or declined etc) of the document can be reviewed.
This site is still at beta stage and you can give it a by signup for free.