Well, I have a Samsung 204B 20.1 viewable area monitor and it seems to do me pretty good until I get that upgrade itch. I have had it for awhile and it works just great. Though nowadays you can get ones like the 226BW 22" which I have read is pretty good for gaming and all around and you can get it for pretty good prices if you shop around.
Mine happens to be a 4:3 monitor which isn't widescreen but it's ok I game at 1600x1200 resolution just fine. That 226BW is 16:10 it's widescreen @1680x1050. I'm currently looking at the 245BW from them as an upgrade option which is 24" widescreen at 1920x1200.
Best Bet is to google around on the companies that morbid mentioned too, look at reviews and prices for each in the range you need, then make a choice.
