Honestly, it might seem like a lot of effort but an RGB>SCART cable and a 4:3 LCD TV/monitor with SCART will cost you under £20 and is by far the best solution. Computer LCD monitors are a pain to get working with Amiga's, more often than not they require an expensive scan doubler/flicker fixer. Seriously, it might seem like a pain but the solution people are already offering is the best, easiest and cheapest. Walk in to any Cash Converters, or similar, they always have dozens of old LCD TVs for a tenner.
EDIT: Here you go:
http://www.ebay.co.uk/itm/281459485400