Alasdair,
every time i go to show my mates you website it is down! It's OK, I have explained the site is great but the webhosting package is not. Presumably, your advertisers will be getting a bit hacked off with this so I'm sure you will be doing all you can to get it sorted. Best of luck. I will hold fire on the word of mouth recommendation until you feel that you have found the solution.
Keep up the good work