While death knights have only been around for a couple of years and retribution paladins are tasked with rediscovering themselves every few months, rogues have remained consistent throughout WoW's entire lifetime. We've obviously received tweaks and changes along the way, but the rogue of today looks an awful lot like the rogue of the past. Over the years, the rogue class has been dissected from every angle, and our studious brothers and sisters of the shadow have discovered its secrets.
There are three main areas of rogue research: mathing out how the class works (and yes, mathing is a verb), picking the right gear, and figuring out the best specific strategies. The best and brightest rogues are constantly monitoring our DPS models to ensure their continual accuracy, compiling lists of the best gear and how to get it, and detailing their guides for dealing with players and raid bosses alike. I can say with a tremendous amount of bias that Encrypted Text is the best source for rogue info, but of course there are other sites that are useful as well.
While I know plenty of rogues are content with BiS lists and simple rotation guides, the fact is that without math, we wouldn't be able to know what pants are the best to wear or when to use Rupture. Every aspect of rogue life is dictated by numbers, as we're always striving to be the best we can be. As a pure class, our usefulness is measured by a single stat: DPS. Figuring out how our DPS model works is paramount to ensuring that we're doing everything right.
The best place for theorycrafting discussions about any class is Elitist Jerks, and rogues are no exception. Aldriana and many other fine rogues are constantly testing mechanics and procs, comparing notes on gearing strategies, and examining patch notes and changes. If you want to be on the bleeding edge of rogue theorycrafting, simply subscribe to a few of the rogue threads and check in regularly. I recommend not posting at all for at least a month or two, even if you think you have a good comment or question. Elitist Jerks' quality is due to its strict rule enforcement, and it should stay that way. There are a ton of friendlier places to ask for advice, including the comment section here.
One key result of the work done at EJ are the guides for combat, assassination, and subtlety rogues. Written for rogues, by rogues, these compendiums detail every aspect of that spec's mechanics. The guides cover talent and glyph selection, gear modifications, rotation specifics, and analysis of the spec's role and capabilities. Because of the focus on accuracy over style, these posts are considered to be canonical guides to the class itself. If you play a rogue, read the guide for your spec, and then read the other two. Every successful rogue learns how to play the class from somewhere, and the EJ forums have guided more rogues towards their goal than any other resource.
While theorycrafting is nice, it's pointless unless it can be put to practical use. I constantly see requests from rogues for stat weight charts and BiS lists, and I simply don't understand why you'd want either of these things. Infamous rogues Aldriana and Antiarc combined to give us Shadowcraft, by far the best theorycrafting and gear selection tool ever developed. From Shadowcraft, your every question about rogue DPS is answered. You can figure out how potent a given talent spec would be, you can pick out what gear makes the most sense for you, and you can ensure that all of your reforging and gemming is done properly.
All of the knowledge that used to be constrained to spreadsheets and calculators is now available in an automated web system, with Armory integration and seamless updates. While there will always be a place for sites like ShadowPanther and Wowhead to figure out how to acquire gear, your gearing decisions should always be run by Shadowcraft first. ShadowPanther and Wowhead's EP/AEP system is great for one-time analysis, but the truth is that our stat weights shift with every change we make, and only Shadowcraft can reflect that in real time.
If you're not using Shadowcraft today, stop what you're doing and go check it out. (Come back when you're done, though.) It's everything that a rogue could ask for, and it lets us make intelligent gearing decisions without worrying about relying on outdated information.
Learning to play
You know what they say about the best-laid plans of mice and men. Even though we know how rogues work in theory and we can pick the best gear out of a lineup, that doesn't help us topple raid bosses or thwart enemy players. In order to make the right moves in any situation, you need experience. While it's impossible for every rogue in the world to play with DREAM Paragon and to reach gladiator status, we can pool our collective knowledge together to improve rogues at every level.
For raiding rogues, there are a variety of resources available. Elitist Jerks, of course, maintains a great thread that details rogue-specific fight mechanics -- what can and can't be Cloaked, when to Feint, and other specifics. I try to cover much of the same material in my boss guides here at Encrypted Text, adding in any tips or tricks to maximize your DPS or how to utilize the fight's mechanics in your favor. Learn To Raid and TankSpot are my two favorite sites for general raiding strategies, as they let you get a first-person view of the encounters to prepare yourself.
When it comes to PvP, there isn't a site that can compete with Arena Junkies for rogue information and tactics. I often refer rogues to Riosan's great rogue Arena guide, and there are plenty of skilled rogues posting their thoughts and secrets for success. Rogue PvP is a hard topic to cover, as PvP tends to be highly dynamic and varies so much based on the situation, the environment, and external circumstances. The best any rogue can do is to enter combat with as much knowledge as possible and then focus on making the right decisions with that knowledge.
Bringing it all together
If you have a specific question or need, it should be easy to find the info you're looking for. The problem is that you don't know what you don't know, and so you never know if you know everything. In order to ensure that your rogue knowledge is complete as possible, it's important to keep up with the community and to continually consume new information.
Rfeann curates an amazing list of questions and their answers over on the official rogue forums, and the material there could keep you reading about the class for days. While Elitist Jerks frowns on threads and posts that veer outside the realm of absolute necessity, the official forums are a place for open discussion amongst rogues at every level and of every playstyle. One of my favorite threads of all time is the Ganker's Kit of Ganking, which wouldn't even make it past the moderators at EJ. The official forums aren't well tended, but that allows for you to get a feel for what the community is really thinking. I got my start in rogue theorycrafting on the official rogue forums, working with my friend and rogue mentor Dask to answer questions and talk shop.
Obviously the sites I've listed here are only a few of my favorites, and there have been many resources that have come and passed over the years. What are some of your favorite places to learn about the rogue class? Where do you turn when you need a question answered?
Sneak in every Wednesday for our Molten Front ganking guide, a deep dive into the world of playing a subtlety rogue -- and of course, all the basics in our guide to the latest rogue gear.