What good alternative donor cars are there?

[brainbug007]

Hi everyone! I'm very new to car building and really like the prospect of building my own using the haynes roaster book. I've ordered the book and have started to dig around for a good donor and everywhere seems to suggest that I use a for sierra but there doesn't seem to be very many of these around (only 1-2 showing on autotrader). Can anyone suggest any good alternatives and how what would be involved roughly with using it over the Sierra. Also, is it better to ensure I buy something that's still running at the moment or try to buy each bit separately from somewhere like a junkyard?