There is a lot of "useful stuff" out there that can really help improve your playing techniques and there is other stuff that is just, well..useful! Here are some bits and pieces that I think you might find useful....
Damn useful this - its a software metronome that you can run on your pc! http://www.nch.com.au/metronome/
More Free Guitar Resoures
onlineguitarlessons.co.uk is a website designed to help you learn guitar for free.
They have a full range of lessons ranging catering for the beginner right through to the advanced.
Check them out!