There are basically three types of LCD panels in the market:
1. TN - Have fast refresh rates, but poor viewing angles and colours.
2. MVA or PVA - Great contrast ratio and viewing angle, but poor real refresh.
3. IPS - Good refresh, good viewing angle, good colours (best all-round).
Every panel out there will have one of the above panels inside of the bezel, but it is quite hard to find out which one has which type. For all round best performance including photography, IPS is the best. However, some of the MVA/PVA panels have good colour as well. The only problem with *VA panels is that they often have a purplish/magenta hue to them.
Spend some time reading the following guide, it is very informative:
And then look through this article which reviews some current 19" LCD's:
Basically, stay away from the 8 and 12ms panels, as those will definately be TN. And, if you want to avoid the MVA/PVA panels, stay away from panels advertising 800:1 or better contrast ratios. Besides accurate colour, the most important spec of an LCD is the viewing angle (in terms of photography).
There are some good panels out there for photography, but it'll take some effort to find them.