How do we know the prize in FG of each item...is there a list or something?

Best thing you can do is to make a Price Check on your realm. If you don't know how to, check this out:

How To Post Correctly With The New Update.

This post was edited by Nerubian on Aug 5 2011 05:28pm

There are price guides in some of the trading forums. You can also make a price check topic and see what people think.

Do you mean price?

If so then usually there is a price guide you can refer to stickied in most of the Trading Grounds.

You can also post your item in the Price Check tab to get opinions on what it may be worth, nothing has a set price really.