Societies, journals, and other resources for linguistics students:
The Linguist List: one of the largest sites with many links and with mailings to subscribers on topics of interest to linguists concerning jobs, book reviews, graduate and undergraduate programs, conference announcements, requests for information, etc.
Linguistic Society of America: truly the international society for linguists, with a large site with definitions of all the sub-fields of linguistics, a program directory, resolutions of the society on public language matters, a list of linguistics journals, links to affiliated organizations, etc.
Center for Applied Linguistics: many practical links and information on bilingual education, literacy, foreign language and ESOL instruction, testing, instructional and research materials, newsletter, etc.
Summer Institute of Linguistics: another practical site with software, downloadable fonts, information on language learning, literacy, translation, and sociolinguistics.