I downloaded Deciphers LOTRO Program and even though I can't play there (I have no account either) I use it's offline features, such as it's deckbuilder. It's very easy to build decks there, I can easily look through all the cards or search the one I need. Once I make a deck there, I just put all cards together using GCCG's decbuilder.
GCCG's deckbuilder is quite good actually, once you learn to filter cards. The only thing I mind is that cards have to load every time you check out the collection so it takes more time. You can load entire database at once (that takes about 1-2 min on my computer), but since I usually use /find command, it's not necessary.