you could try http://www.w3schools.com/js/default.asp. it's a very basic intro to the language.
Also I would recommend JavaScript: The Definitive Guide
very nice book, describes the language in details.
Also Douglas Crockford's JavaScript: The Good Parts
And probably some good blogs:
http://www.catswhocode.com/blog/
http://net.tutsplus.com/
http://www.webappers.com/
for exercise I would recommend jsFiddle