I agree that keeping track of card errata can be a pain.
My playing group made a virtual set that we play with that addresses this. If you are interested in what we did in this virtual set, just let me know and I'll e-mail (or pm) it to you. [I created a "
Bag End" forum topic called "A fun way to play" that explains this in detail].
Otherwise you can probably just search the card database for the word "Errata".