Today’s legislation lags behind the needs and practices of the Internet, electronic governance and digital economy in general. It is widely believed that enhancement of the legal system with IT to facilitate law-making and law enforcement can contribute to improvement of business and social environment, as well as people’s quality of life. Our paper is a study of foundations and means for building Legal Knowledge-Based Systems and transition to the so-called computational law. Particularly, we outline the application of legal and regulatory documents indexing technologies for legal language processing (LLP) and construct domain ontology for real estate legislation. The implementation of the approach may decrease the number of errors, over-complexities and ambiguities in legal texts, allow automated search for relevant documents, and categorize complicated legal relations. These should save the practitioners from spending too much time on routine tasks, simplify decision-making in law enforcement and reduce the subjectivity, and ultimately contribute to creating uniform and consistent legislation.