In reply to Indy:
What kind of running? 10ks, marathon, trail?
These are the main blogs I follow which are all centred around trail/ultra running (and a shameless plug for mine at the end).
http://www.irunfar.com - well established ultra running blog from the US.
http://www.mudsweatandtears.co.uk - a lot more UK focussed - lots of event news.
http://sarzmountainrun.blogspot.com - north wales based trail runner. Sometimes posts here.
http://eryridiaspora.blogspot.com - IainR from these boards
http://trailjunkie-phil.blogspot.com - experiences of a British guy taking up ultra running late in life on the Cote d'Azur.
http://runlonger.blogspot.com
http://itsallaboutthevertical.wordpress.com
http://chamoisbotherer.blogspot.fr - trying to pass on what I'm learning/experiencing running in the mountains, but not updated nearly enough.