1. A method of adding a word to a speech recognition vocabulary, comprising: receiving a spelling of the word, receiving an utterance of the word, creating a collection of possible phonetic pronunciations of the word by: comparing the spelling to a rules list of letter strings with associated phonemes, wherein the comparing includes searching the letter strings of the rules list for a letter string from the spelling of length greater than one letter, and limiting the collection of possible phonetic pronunciations to phonetic pronunciations containing phonemes associated with the letter string of length greater than one, using speech recognition to find a best-matching pronunciation from the collection that best matches the utterance of the word, and adding the word to the speech recognition vocabulary using the spelling and the best-matching pronunciation.