I agree, I think it's a very bad idea to take out a loan to do a PhD. It is not worth the investment/risk.
If you haven't got a scholarship, probably the best thing to do is do the PhD part time while working and/or seek out small charity grants to cover some of the costs. But please do look into whether or not the PhD is worth your efforts before you start.
There will be student loans for UK PhD students in future, but details and dates haven't been confirmed. Possible that they'll be available by 2017-18, but by no means guaranteed.
There's a guide to what we know so far over at FindAPhD:
Hi Mark_B, I went through future, but their loan quite expensive, if i take £12000.00, (for three yrs tuition fees) I need to repay £19980.01 over 10 yrs..