On-line Map of Languages Spoken in US

The Modern Language Association's Language Map displays the locations
and approximate numbers of speakers of the 30 languages most commonly
spoken in the United States. Any search you perform will include a list of all languages spoken in the state, ranked by number of speakers using 2000 Census data. For example, more than 19 million people in California speak English; nearly 12.5 million speak languages other than English. Spanish speakers (more than 8 million) lead the list and Navajo speakers round out the list with about 1800 speakers across the state.