I'm certain that Dawson was £3m as he was part of the Andy Reid deal, and Reid was 5m. Bale was ranging between £5-7m I believe, Crouchie was £8m and i'm not too sure on Defoe, as he was supposedly £15m, but Portsmouth hadn't payed us fully for him but im not sure :S.
Bale's deal involved add-ons which I am assuming he has/will fulfil, taking it to around £10 million total. Defoe was supposed to be around £15 million, but Portsmouth owed us money still, so it was deducted from the 'official' fee.
Crouch's fee seems to range between £8 million and £10 million, depending on who you ask, so I accounted for the more expensive end of the spectrum, and I wasn't sure about Dawson's fee, so I just stuck a number in from the first source I found.