Amazing how much confusion there still is over this.
The Polish broke the 3-rotor Enigma in the 1930s - thanks, in large part, to the spy Hans Thilo, who provided code books. The main figure in this was Marian Rejewsky whose team worked for the Biuo Szyfrow,
The bomba was invented then.
When it became clear that Poland would not last long, the Poles - to their eternal credit - arranged a meeting with the French and British and handed over everything they had.
(Incidentally - and not much of a reflection on the powers that were - Rejewsky made it to England, but was never allowed to work on Enigma by the British...)
At Bletchley Park this work was extended, in partcular with the bombe, designed by Alan Turing and Gordon Welchman.
Colossus was designed (by Max Newman, Turing's supervisor at Cambridge) and built at the PO Research Station at Dollis Hill, by Tom Flowers, Sid Broadhurst and W.W. Chandler.
It was NOT designed to crack Enigma, but to crack "Fish" a teleprinter-code used for sending strategic, rather than tactical information.
Alan Turing was NOT involved in the design of Colossus - he was in Washington DC at the time.
And, oh yes a codebook was indeed rescued from a sinking U-boat - at the cost of at leat one British life.
Put not thy trust in Wikipedia or the American notion of history. (After all, in "The Burma Story" Erroll Flynn apparently defeated the Japanese in Burma single-handed - despite the fact that no US troops fought in Burma at all).
Hell, what did Henry Ford say about history?
Perhaps more to the point is what George Santayana said...
All of this information is readily available - particularly in Hodge's magnificent biography of Turing and on Tony Sale's codeberakers' web site: http://www.codesandciphers.org.uk/