From what I've seen Google doesn't contact people :) My guess is they also have a policy of not sharing reasons for getting blacklisted, to ensure they're not giving spammers an easy way to fix their website.
They claim they respond to all "Site reconsideration" requests. I had to file one once, they did respond, but with a very non-informative and unhelpful response.
https://github.com/alexblack/google-fastbutton
It works crossbrowser (e.g. doesn't break) and has a few tweaks including a hook for jQuery and xui.js