At the bottom of the documentation for hashlib, there's a link to
http://www.cryptography.com/cnews/hash.html

which the hashlib documentation describes as "Hash Collision FAQ with information on which algorithms have known issues and what that means regarding their use."

However, the page at that link is identical to http://www.cryptography.com/

which is just the homepage of some company that happens to deal with cryptography.  If they do in fact host a Hash Collision FAQ, I couldn't find it. :-(

Googling for "Hash Collision FAQ" (with quotes) mostly turns up references to the Python documentation, so I'm guessing the intended document no longer exists.

The following wikipedia link might be an OK substitute, although it makes for pretty dense reading.
http://en.wikipedia.org/wiki/Cryptographic_hash_function#Cryptographic_hash_algorithms