In NwN you can put points in the skill Lore at level ups, which is the skill used for identifying.
There are items that grant you a bonus to lore which helps you identify.
Futhermore - there is a poition of Lore, which when you drink it, will give you a short boost of Lore so you can identify items. (Pause, after drinking, and you can identify more items

).
There is also a spell for the same purpose called Identify.
You can also pay merchants to identify items for you, when shopping at their store.
Lastly - I know in the expansions (SoU and HotU) you can get some of your henchmen to try and identify items for you. (Specifically a bard henchmen). I don't know if this works in the original NwN, because I've never played that campaign through using the bard henchman. But this is done, by starting a convesation with your henchman.
Hope this helps.
edit: danged - Guada was faster
