Any divination depends heavily upon the interpretation of the symbols. Whether pictures on cards, dice rolled, or stones thrown, you glean insight through the symbols offered through the randomness of the layouts. The symbols on real cards as opposed to electronic cards are the same. I see no difference.
The cards themselves do not hold any power. Whatever insight you gain comes from interpretation. With e-tarot card spreads, you need to be able to consider what the web site interprets as opposed to what perceive as being true.
You must consider the outside forces that influence as well as the forces from within. For example, reaching a goal may not depend on luck as much as recognizing a fear of failure. We humans carry tons of emotional baggage that often prevents us from enjoying our lives. Whatever interpretation of the cards, consider your own fears and inhibitions that might be holding you back in the symbols.
My favorite e-tarot is Llewellyn’s page. They offer a number of decks to choose from, and a good selection of spreads. You can opt ‘no reverse cards’, as well.
Personally, I like any deck other than the Waite-Rider deck. Its a bit heavy with the Christian view in its interpretation, and the Shapeshifter deck offers more in the way of positive spins on even negative situations.