If you've read Richard Knaak before and enjoy him, by all means, give them a read. I really am not a fan though, so I'd personally say give that trilogy a pass. If you do read it, reading Day of the Dragon first may be wise, but not mandatory. The trilogy takes place after that and heavily uses Knaak's own characters, rather than Blizzard-made characters, so they're not something you would have learned about in WoW or the other Warcraft games.
Along the coastline in the Swamp of Sorrows there are skeletons of giant turtles with structures built onto the back of their shells. Is this a nod to the Gnome submarines used in Warcraft II? If I remember correctly, they were turtles as well.
There are many Warcraft novels on the market. Are they a good source of canon lore, and if so, in what order should I read them in? Why do Gnome NPCs sometimes say "Daylight's burning!" as a greeting? Seems somewhat odd for a generally cheerful race. A reference to Gnomeregan, or because they lived underground and now they're scurrying up top with all the other races, perhaps they're a little photosensitive?
Well, hehe, I don't think they mean it in a "Your star burns!" kind of way. It's an expression that means something like "you're wasting time!" Sort of how Goblins say "Time is money." Hurry up, don't dilly dally, that sort of thing.
You're going to get mixed answers on this one, so perhaps our readers will give you a second opinion on it after my answer. Speaking strictly of the novels, I definitely recommend Beyond the Dark Portal, Rise of the Horde and Lord of the Clans. That's the order I would read them in, but any order should be fine. They're specific points in history, but there's enough of a gap between them that chronological order isn't mandatory. They weren't even written in that order, so it's no big deal.
I don't personally enjoy Richard Knaak, but Day of the Dragon is worthwhile simply because it sets the stage for a few things and gives you a little bit of understanding of why the Red Dragonflight and the Kirin Tor are buddies up in Northrend beyond "the Blue Dragons are killing our mans." Plus, it's one of his earlier Warcraft novels, so Rhonin isn't a complete joke in this one yet. I would not read the other Richard Knaak novels if you're looking for anything canon. The War of the Ancients is an event that happened in Warcraft lore, but Knaak's telling of it in the War of the Ancients Trilogy is not entirely canon, according to a Community Manager's post on the WoW forums sometime back.
While yes, the Gnomes did use the turtles as submarines in Warcraft II, they aren't the only ones that have made use of them. According to a few quests in Darkshore, the Naga have put the Giant turtles to work as transports. Also, in Wrath of the Lich King, the Tuskarr use giant turtles with carriages on their backs as transportation as well. In fact, you can use them to get from one end of Northrend to the other. Edit: I was wrong, the Gnomes didn't use the turtles. It was a Horde unit. Same answer applies, though.
The rest of the novels are sort of take it or leave it. They give you a good background of the lore, but I wouldn't call them must-reads. I recommend them, but you won't die if you don't pick them up. Cycle of Hatred in particular was not something I would read more than once, but I am glad I read it that one time. I wouldn't tell you to not read any of them, but some are definitely much better than others. The War of the Ancients trilogy is decent fan service if that's what you're into, but the events are non-canon and it's so gratuitously fan-servicey it makes me a bit ill. The rest is up to you.
They've done a pretty good job of making the various novels independent of one another, so you don't need to read them in chronological order unless they explicitly state which order they go in, like the aforementioned trilogy. Don't worry about what comes first otherwise. Pick out whichever ones look most interesting to you. wowgoldsell has a full listing of all of the current Warcraft novels.
primary email here kevincoin@gmail.com