So I don’t much hold with videogame tie-in books, but David Gaider’s Dragon Age: The Stolen Throne and Dragon Age: The Calling got a bit of special dispensation by virtue of a) Gaider being the lead writer for the game, so someone who is creatively interested in the milieu and not just a hack cashing in, plus b) Dragon Age maybe being the best videogame of all time.
So how were they? Well, let’s calibrate first: They’re books based on an RPG setting, like all those Forgotten Realms and DragonLance books. If we measure by that standard, they’re superb, among the best books I’ve ever read. If we measure them by regular-novel standards, they’re... not bad. The Stolen Throne in particular is actually a reasonably well-crafted novel that would appeal to fantasy fans.
But for the most part, if you’re just looking for fantasy, there are better options. The real reason to read these is if you’ve played Dragon Age and gotten deeply enmeshed in its world and characters, in which case there’s some interesting stuff here for you (The Calling seems to be setting up the conflict in the upcoming expansion, even; it’ll be interesting to see how that goes).