A few points...
Go with a semi-major brand - ViewSonic, Samsung, NEC, or similar. I routinely see these going for about $600 in the 19" range, 3:4 aspect (like your TV.)
When you get it, LEAVE IT ON for a solid week. Why? This is burn-in time, you will catch any semi-dead pixels or control electronic problems quicker this way. Feel free to use it, just DO NOT TURN IT OFF.
Don't worry about anything 'exotic' - like that Mac display you were shown a couple posts ago. That's an example of a 16:9 aspect display - while that's not a bad thing, it will cost more. It's geared more toward graphic designers or video editors anyhow. If you're a regular computer user (like meself) a 3:4 display is just ducky.
Take the time to check out Best Buys - I have to admit, their pricing is usually great. Also, if you have enough electronic shops about, you might be able to find "white box" units (name-brand refurbished) that will save you a few shekels. Make sure they're majors, and make sure they have a warranty (the major refurbs usually will.) Cosmetic defects are farily likely, but the innards are almost always brand spankin' new - and isn't that what you want anyhnow? Same burn time on refurbs as new.
Going in the 18"-19" range, I'd be surprised if you had to spend more than $800 (I padded that since I'm in the SF Bay Area/Silicon Valley - you can't throw a rock without hitting a computer company here... I'm not sure where you are - but I mentioned Best Buy because their prices here are good, and have been everywhere else in the country I've been!)
5-90