Some of her emails are here. I searched for "Cameron" and got some moderate gems (see below). I am pretty sure that Clinton calls Cameron "wacky", but you can read the email yourself below. And she felt sorry for David Miliband in 2009, when a number of people were out to get him.
For anyone interested in reading the searchable private emails of one of the most powerful people in the world in modern times, this is a great resource. You can follow the ups and downs of Tony Blair's attempt to become President of Europe. You can .... well, I leave it to you.
On 26 November 2009, Sidney Blumenthal told Clinton this (about the lack of British trust in the US and the 'Special Relationship' post-Iraq): "The US administration is considered blinkered, parochial and counter-productive. Conservatives are more
contemptuous than Labour, which feels abandoned and somewhat baffled. Rather than eager to be Obama's poodle,
Cameron would be superficially friendly and privately scornful. Class has a lot to do with the contempt. A Cameron
government would be more aristocratic and even narrowly Etonian than any Conservative government in recent history,
sharply contrasting especially with the striving and classless perspective of the grocer's daughter, Margaret Thatcher." Clinton forwarded that message to some State Department colleagues (including Richard Holbrooke) on the same day.
Here's another Blumenthal email with the subject "Miliband" dated 22 May 2009:
"Hillary: Spoke with Jonathan Powell. What we heard is accurate. ... The plot (sounds like the Tudors): David is the target, from
multiple angles and motives, personal ambition mixed with anti-Blairism. ... Ed Balls,
one of Gordon's closest longtime advisers, is also determined to topple David. Balls is a contemporary of David's, wants
to be leader of the party himself, and continues the Gordon v. Tony bitter rivalry into the future. ... If Gordon names Peter to David's job, Balls would take
Peter's and become Business Secretary. David would be pushed into Home Secretary. Once Balls takes Peter's job, Balls
will likely reverse Peter's privatization proposal for the Royal Mail to win support from party's left-wing base, beginning
of his campaign against David for post-Gordon leadership struggle. Tony sees the situation as terminal. Hope to speak wi
th him soon. He is trying to become President of Europe if and when Lisbon treaty passes. ... There's more for when we can talk. Sid". Clinton's response? "Very sorry to read this confirmation."