Textbook and accompanying website links
Linguistics: An Introduction by William B. McGregor. 2009. Contiuum Publishing Group.
Accompanying website to the textbook:
http://mcgregor.continuumbooks.net/

Video clips of some animal communication systems
Spiders courtship gesturing
Fiddler crabs claw-waving
Bees dancing
Conversations with KOKO

Language and the brain clips
Broca's aphasia

Wernicke's aphasia
PET scan experiment

Language acquisition clips
Wh-doubling in children's speech (from work by Stephen Crain, Rosalind Thornton, and Graciela Tesan)
Swedish negation in child English
(from work by Stephen Crain, Rosalind Thornton, and Graciela Tesan)
Berko's wug test (with Rosalind Thornton)
Video clips of Christopher, the polyglot savant (from work by Neil Smith)

Sociolinguistics clips
Do you speak American? Test your vowel power!
Northern Cities Vowel shift clip with Labov
American English dialect map clip
Bert Vaux' dialect survey and maps

Linguistic profiling study
Linguistic profiling ad
Jeopardy with a new twist
An excerpt about linguistic discrimination against AAE speaking students
History of AAE

Other useful links

Ethnologue: An encyclopedic reference work cataloging all of the world’s 6,912 known living languages

The Universals Archive of Universität Konstanz. : A huge list of linguistic universals that have been suggested in the relevant literature, in particular those of an implicational kind.

SIL: Summer Institute of Linguistics

Endangered languages:The SIL webpage on endangered languages.

Software tools: Computer resources including an extensive library for language researchers and software tools and fonts.

The Linguistic Soceity of America