Do you mean the Pennine Bridleway or the Pennine Way? As far as I know the Pennine Bribleway is not yet complete but you can do the Southern section from Hartington, or Middleton in Derbyshire to the Mary Townley Loop which it joins just north of Rochdale at Summit. The bits further north are partly signed etc so you could probably work it out from the info you can get via Google. I've cycled the whole Mary Townley Loop in a day (45 miles), - it goes past near my house, and walked parts and other bits further south. A while ago I met a bunch of guys on bikes at Widdop who had cycled from Derbyshire, were intending completing the loop and cycling back. They were using B&B's. The Bridleway is obviously set up for horseriders and cyclists so is never too bad underfoot, and often surfaced to accommodate horses/bikes. It does go up and down a bit though. This guy gives a good account of the Mary Townley Loop from a cyclists perspective so you'll get the idea:-
http://www.idonohoe.com/mountian_bike9.htm If however you mean the Pennine Way, many on this forum (including myself) can give you advice about that and if you search through this forum, you'll find quite a few accounts and bits of info.
Also look at the National Trails website at :-
http://www.nationaltrail.co.uk/PennineBridleway/downloads.asp?PageId=36 Hope this helps