A few psycholinguistic sites around the web.
NB. Some of these links no longer work. I’m slowly going through them. Sorry!
If you're looking for something relatively specific, though, you can't beat Google.

@ York
The Psycholinguistic Research Group @ York is where you'll find details of my collaborators here at York, including postgraduates (for US speakers, 'postgraduate' = 'graduate student'), postdoctoral researchers, and faculty.

There's also a large group interested in disorders of language development, with interests in dyslexia, language in children with autism spectrum disorder, and other cases of disordered language development. The group is called the Centre for Reading and Language, and is one of the leading groups working on dyslexia. Aside from their first-class research, they are also extremely good at assessing children and making appropriate recommendations on how to proceed if your child has a language problem.

My 'official' webpage can be found on the York departmental webpages.

Specifically Psycholinguistics
This is a Psychology of Language Page of Links. It's quite comprehensive. I'm ashamed to say that I "borrowed" one of my background textures from that page.

Language and Linguistics - glossaries
Xrefer.com is a very useful site for looking up dictionary-style definitions of linguistic (or any other) terms.  There are various 'glossary pages' elsewhere on the web that are more specifically linguistics or psycholinguistics oriented, including the Lexicon of Linguistics and SIL International; and these two more computationally-oriented glossaries provided by Parsifal Software and Bill Wilson.

There are several on-line dictionaries that all do pretty much the same sort of thing.  So if you don't have access to the Oxford English Dictionary on-line, try the following: your dictionary; allwords.com; dict.org; or Merriam-Webster. You might want to look at wordnet also, although it's not really a dictionary as such. There are various versions of Roget's Thesaurus 'out there', and this rhyming dictionary isn't bad either. If you'd like to receive 'a word a day' in your email, then you could try wordsmith.org.  They also have a useful anagram solver (to the extent that such a thing can be useful...) If you are interested in etymology, eleaston.com has some excellent links to online etymology sites (as well as to word-a-day sites and various others). 

This is a really useful site with links to pages that describe/teach the grammars of (some of) the world's languages.

Psycholinguistic Journals
These links to psycholinguistic journals are fairly good, but there are several journals that contain articles with psycholinguistic content but which are not language-specific and which do not, therefore, appear here (such as Journal of Experimental Psychology, to pick one example).

My own most-used links
I also visit the BBC news page, the travelex currency converter (based on the tourist rates), the on-line British Rail timetable, Virtual Florist (they do real flowers too), and for travelling, Expedia (whose customer service is excellent - I've linked to the uk site, but simply replace the '.co.uk' with '.com').  And of course, Amazon are fantastic for books.  As a Mac enthusiast, I recommend versiontracker for software updates, and MacOSXHints for hints on how to use OS X. And if anything goes wrong with your Mac, seach MacFixit first.