=============================== Websites ==========================

    http://wow.tcgplayer.com/db/Cards.asp?SetName=Heroes%20of%20Azeroth
    http://pojo.com/warcraft/cotd/index.shtml


=============================== Specific cards ==========================

Forbidden Knowledge
    1) It lets you pick the specific card you want to use, rather than drawing randomly
    2) If your opponent does a "destroy ability" on this card while your deck is removed from the game, you're potentially very screwed.
        2a) Blueleaf Tubers is very important to have in hand, as one possible counter to this.
    ....

Lady Jaina Proudmoore
    Wow: All other allies literally can't attack anyone on your side.  However, this card can be gotten rid of by:
        - the other hero attacking this card
        - doing direct damage with abilities
                                http://entertainment.upperdeck.com/wow/en/news/article.aspx?aid=1154

Valthak Spiritdrinker
    Your hero can go to -10, even -20 damage, but won't die until this specific ally is killed.

Hannah the Unstoppable
    It sounds like most people are playing this card to mean that all of the opponent's PROTECT keywords are nullified, regardless of who is attacking (eg. it doesn't just apply when Hannah is attacking)