A Google custom search engine for Python has been made available by Gerard Flanagan, indexing:
To refine the search to any of the individual sites, you can specify a refinement using the following labels: stdlib, wiki, pypi, thehazeltree
So, to just search the python wiki, you would enter:
somesearchterm more:stdlib somesearchterm more:pypi somesearchterm more:thehazeltree
The Hazel Tree is a collection of popular Python texts that I have converted to reStructuredText and put together using Sphinx. It's in a publishable state, but not as polished as I'd like, and since I'll be mostly offline for the next month it will have to remain as it is for the present. However, the search engine is ready now and the clock is ticking on its subscription (one year, renewal depending on success of site), so if it's useful to anyone, it's all yours (and if you use it on your own site a link back to http://thehazeltree.org would be appreciated).