Here are some links to some of the websites I regularly visit, and some links that I send students too.....  in no particular order ... I'll keep adding to it too!

Beartramka Music - Danielle Perrett and David Gough - I love their music, and so do my students... and much of it is in the Trinity College syllabus.

Fingerless Wristies - I love these (and I have to admit to have several pairs, and living in them for the most of winter!!!  Kate Watts makes them beautifully!

This website, and their newsletters, are so great - full of learning and teaching tips, downloadable music and they hold an annual harp weekend that I so want to go to..
http://www.southeasternharps.com/southeasternharps.com/Home.html

This is the metronome I have on my computer - very easy to use - I find I use it often as I always know where it is!
http://www.nch.com.au/metronome/

The Edinburgh Harp Festival - I last attended in 1997 and its on my bucket list to go again. Its a great website with lots of interesting news about the Scottish harpers and they have just started putting up a downloadable tune each month!
http://www.harpfestival.co.uk/

Traditional and contemporary celtic music - dots and MP3s    
http://thesession.org/

Teaching intervals using songs?  Perfect 5th = Twinkle, twinkle .... this is an advanced version of this concept.
http://www.youtube.com/watch?v=dF074CL5vjI

This is brilliant! Download an MP3 into Speedshifter and then you can change the tempo of music to a speed where you can play along. And its free!
http://nz.abrsm.org/en/exam-support/practice-tools-and-applications/speedshifter/

This is a great website for finding theory worksheets for kids - I think Susan Paradis must be an amazing teacher!!
http://www.susanparadis.com/

The Axis of Awesome - very clever guys - wait til you hear them doing several songs all at once!   Chords I V vi IV (1, 5, 6, 4) in that order.
http://www.youtube.com/watch?v=oOlDewpCfZQ