1. A method of generating domain-specific grammar rules using a computer system having data processing logic, the method comprising: parsing a plurality of documents stored in a digital document database on computer-accessible storage media to identify key terms of each document based on sentence structure; extracting a plurality of n-grams from each document, wherein one or more of the n-grams include spaces and partial words; extracting a frequency of each n-gram in each document; extracting a frequency of each n-gram in the plurality of documents; assigning a novelty score to each of the n-grams in each corresponding document, said novelty score representing and being based on the extracted frequency of the n-gram in the document and the extracted frequency of the n-gram in the plurality of documents; determining which of the extracted n-grams are in each identified key term; assigning a weight to each key term based the novelty scores assigned to at the extracted n-grams in the key term; and generating the domain-specific grammar rules for a speech recognition engine, said grammar rules including said key terms in association with respective probabilities based on the weights of the key terms, wherein the key terms define phrases that are likely to be spoken from the plurality of documents, and the grammar rules define which of the phrases are likely to follow others of the phrases with the likelihoods defined by the probabilities.