Try using the 'search' function both here and on the D&G forum, look for posts by redsnail and/or myself, and you ought to find there are several long and detailed posts explaining the entire process.
The very short version of the answer is, about 6 to 9 months of time and around £20,000 worth of money. Resits of all the written ATPLs, CPL skill test, compulsory training course for the IR and an MCC - very few exceptions can be made unless you have a lot of multi pilot or big jet command time.
Oh yeah, and take my hard learned advice, don't refer to this place as 'England' on the forums or you'll have a bunch of uppity Scots and Welshmen jumping down your throat in short order <img src="wink.gif" border="0">