I use Search Everything from VoidTools to find stuff by file name. For search by contents, I recommend UltraSearch from Jam Software. It would reliably find files that I knew I had *somewhere* on my many drive partitions, even when the search built into Windows 7 could not find them. Very flexible and as quick as I ever needed, without indexing. Both are free. “UltraSearch finds files and folders on local NTFS drives”. TreeSizeFree from Jam Software is also a very good to find which files and folders are taking up space on your hard drive. I have over a million files on my two internal drives, and these programs have saved time and prevented headaches!
As for Search in Contents from MsTech, the comment from JOHANNES has scared me away. I don’t need another autostart program since I don’t search for files all the time. Definitely don’t like the idea of giving up personal information AND access to all my files to a program that is always listening. Am I being overly cautious?