I like Classic Shell menu but I do not find the search engine in Windows that good. Instead I use Everything -
http://www.voidtools.com I know many people who use it
It is very quick and does not need long time like windows to catalog your data. they have sdk which is a wrapper for the Everything IPC.
I wish for Classic Shell to have Everything integration. I looked in their SDK -
http://www.voidtools.com/support/everything/sdk/ It only requires Everything to be installed and running.
Classic Shell will need to have the same privileges as the Everything client, or you will need to call ChangeWindowMessageFilterEx for WM_COPYDATA. Can such integration can be added?