Same. I've downloaded most of the documentation I need to answer day to day questions, and try to limit my use of search engines. Finding most of my answers is faster in the local references I'm familiar. The Internet is my last resort.
I save references I use a lot, like the HTML spec, as PDFs. MacOS indexes these PDF files, so a search in Finder is usually all I need to bring the correct document.
If I can't find a reference locally, or know it doesn't exist locally, I'll turn to the Internet. Once I find the bit of information I'm looking for I'll either save the website as a PDF, or save the info in Snippetlabs or Bear so I can search for it next time I need it.