Hi auldyin
Whatever you do, DO NOT GO TO TISCALI.. avoid like the plague!!! It took me 2 months to switch to another ISP as they do not support migration, and Tiscali tell lies. They say 15 - 18 days.. Well.. it took them 6 weeks to tell BT Wholesale to clear my line, then it was a case of BT clearing their marker, then BT activating the line for my new ISP. If you are under a 12 month contract, you will have to wait til it ends or pay for the months left to run. After 5 years with Tiscali, I checked the original contract and the modem was on loan, BT sent a plastic bag for me to return it to them for recycling.. but I didn't send it.
Look on www.ispreview.com and read the reviews before commiting to any isp.