While a novel, or series of novels, from our favorite grim-dark universe can give us some amazing conceptual inspiration, what if those stories happen to be about the factions or armies we are actually building? Is it possible to use those same books for more specific details?
The basic answer is yes, but let's elaborate with some examples.
My personal favorite Space Marine Legion/Chapter is the Salamanders. I've always loved the stories and fluff behind them, and when Nick Kyme began writing his novels with them as the centerpiece, I was thrilled! I'm also quite lucky in how detailed Nick gets with descriptions in his books. For instance...Chapter Master Tu'Shan
"Tu’Shan sat before him, deep in thought. He rested his broad chin on a slab-like fist encased within a gauntlet of green ceramite. The Regent of Prometheus had received the gifts of his primarch’s prodigious strength and bearing as well as his wisdom. His armour was ornate and finely artificed with iconography of dragons, drakes and other saurian creatures of Nocturnean myth. His hulking pauldrons were fashioned into the image of two snarling lizards, and a thick cloak of salamander hide spilled from his broad shoulders." (quoted from Firedrake)
This is a wonderful description of the Regent of Prometheus! From this text, I know he's in Artificer Armor, and exactly how it's detailed. I also know what specific detail to give his pauldrons, and even more specifically the Salamander Hide Cloak that adorns his armor as well.
Argos, Master of the Forge and Orgento, Techmarine
"Argos inclined his head, setting the servos in his artificer armor whirring again. Unlike the Martians, the pair of Techmarines wore a lustrous green battle-plate. Only their right shoulder guards were red, was Orgento's battle-helm, to show their affiliation with the adepts of Mars. Argos went unhelmeted. Half the Forgemaster's face was obscured by a plate with a firedrake symbol seared into the metal. A bionic eye glared coldly from the socket where the organic had once been. Snaking wires tracked form the device and terminated in plug-like implants in his cranium." (quoted from Nocturne)
"A hulking servo-harness, replete with tools and other bionic appendages, sat upon his back. It gave the Forgemaster bulk and presence, not that he needed it. " (quoted from Firedrake)
This not only gives us an excellent depiction of Forgemaster Argos, but it also tells us exactly how to paint a Salamander Techmarine! We can see the standard scheme of a Techmarine doesn't fit in with the Salamander scheme and we can paint and plan accordingly. This not only helps us with detail, but in turn it helps lend our finished figures a weight and authenticity they may not have had otherwise.
I'll be honest, I could go on for pages on the amount of detail Nick Kyme puts in his novels about the Salamanders. I could also dive into Dan Abnett's astounding level of description, Aaron Dembski-Bowden, Graham McNeill, and more.
"Well what happens if my Chapter/Guard Regiment/Tau Sept doesn't have a novel to provide me with details?"
Then use your Google-Fu, grasshopper. Trust me, there are amazing resources at your fingertips in forums, websites and blogs, you just have to look. If all else fails, make something up! Just be thorough in your background and setting for your chosen DIY and you have the potential to turn out something great. The bottom line is that we play with our toy soldiers in the middle of a richly detailed setting. We should use that setting to our advantage!