I helped a friend clean out his computer after Lop.com "bombed" him (by virtue of him clicking on the wrong link) with a package that made Lop.Com the primary everything as far as the internet software on his machine.
Not only were registry entries very hard to find, I found that 'lop' itself as a word made any seach for 'lop' entries next to useless.
(The 'Lop.com' uninstall was next to useless. No surprise there.)