Cheers guys,, I sorted it today.
I tested the voltage at the starter motor and it was fine, so in a flash of inspiration I connected my jump leads between the -ve terminal on the battery to the engine and it started.
I truly love the internet too... had exactly the same problem today - solenoid click but no start. Used your flash of ispiration, earthed the engine to the battery and it started!! Thanks so much for posting the fix.