If it's any comfort to you, I left Tiscali about a year ago. I had the old Mercury service - but when NTL owned it they kept 194, and 0500 500 194. However, when Tiscali took over, all those numbers were dropped and could only be reached on 0870. Most fo the calls on my bill were non geo numbers - including 20+ minute calls to Tiscali trying to pay a bill. I left becasuse I had run up a bill of very nearly £400, so I paid it as soon as ppssible and cancelled the same day as my last payment. I suggest you leave Tiscali like I did.
Nowadays, if you call Tiscali Broadband, you are not held in a queue, just told to call back later - after you have been chaarged 7.94p per minute AND a 6p connection chage!
The more peopple leave they perhaps may get the message!
Incidentally, if you are told in their letters that yu can get free technical support, and you don't, I suggest you report this to OfCOM for being misleading. Since 1 August, it is up to you of course, who you are with - but this still may be an area that OfCOM can deal with.