I had that, is it just the cable or the actual transformer?
First i bought a universal laptop adapter from maplins (
http://www.maplin.co.uk/module.aspx?TabID=1&criteria=laptop%20universal&ModuleNo=42622&doy=5m7 ) for £29.99 because I was quoted £50 for an official Toshiba one.
The connector on that broke after a few months and I did some splicing with the old connector onto the new transformer and thats been working for the last few months.
I resent it being £30 though, but i had to grin and bear it.