The simple answer is to apply when they start being advertised.. There is nothing wrong with looking around for unis that offer PhD's in your preferred area now and book marking them for potential adverts later in the year.. The whole application thing is a pain in the proverbial so good luck!
Is it really out of the question? It's quite normal to go straight to PhD after the Masters rather than wait a year (I waited a year as it happens - to apply for independent funding - but most people I know didn't).
Not necesarily so, the girl on the computer next to me finised her MSc Sept 2007, started the PhD sept 2007 and graduated last week (Jan 2008). It's worth finding out if you'll be accepted. Then agian you might like to have a post masters break.
Then you need to wait for the next round - later this year but mainly early next. No harm in making provisional enquiries to supervisors that you are keen on though. But much too early for offical applications.
I finnished my MSc in september 2007 and started my PhD in october 2008 but I havent had my MSc graduation yet (will be next month). So you can apply for an october 2008 start if you wanted to.
You can finish a masters and go into a PhD straight away - guessing you just need references from your MA course. I suppose a break may help - but that worries me coz I ma not thinking of taking one!
I am at undergrad level just now with 18 months till I graduate and got my acceptance letter yesterday confirming my PhD for Sept 09 start!! Yes I know - bit quick off the blocks but hey, in this game there is no such thing as too soon.