The LCD monitor MUST have a minimum vertical refresh rate of 50Hz or lower.
99% of LCD monitors have a minimum vertical refresh rate of 56Hz. They work with Amiga's but ONLY in NTSC (60Hz) mode.
You can find them if you look.
The alternative is to buy an LCDTV if you are in europe. They will come with a form of Scandoubler (toastscan) built in but it requires some research to get one which supports RGB on the SCART socket (although I am seeing more and more which do)