Tau fiction can be pretty finnicky. Some of it is good to great, others are downright terrible. Inconsistency is the only constant among the official lore. Also, more stories feature the Tau as antagonists than they do as protagonists.
Personally, I suggest the following:
- Last Chancers: Kill Team by Gav Thorpe (one of the earliest bits of Tau fiction from BL. Imperial, but heavily features the Tau in the latter half)
- Ciaphas Cain: For the Emperor by Sandy Mitchell (Imperial story with Tau (kind of) antagonists)
- Shadowsun: Last of Kiru's Line by Braden Campbell
- Out Caste by Peter Fehervari
- Broken Sword by Guy Haley (found in the Damocles Anthology which has two bad stories, and two good ones)
- Hunter's Snare by Josh Reynolds (the other good story in the Damocles Anthology. White Scars story)
- In Service to Shadows by Joe Parrino (Ravenguard story with Tau antagonists)
I've heard some good things regarding Rogue Star
by Andy Hoare, and the recent Storm of Damocles
by Justin D Hill, but have not yet read them personally.
Some really recommend Fire Warrior
by Simon Spurrier, but I really dislike the novel. It was written congruently with the accompanying game and feels incredibly gamey as a result. It features a shas on his first mission becoming the stereotypical one man army in incredibly far-fetched situations. For early foundations of the Tau, again I recommend Kill Team
Other novels like Fire Caste
by Peter Fehervari, or The Greater Good
by Sandy Mitchell, feature the Tau but (despite the titles) they do not take a central role in much of the story. It also features a generally disliked notion of the Por becoming megalomaniacal warmongers without proper supervision (this behavior is also featured in Black Leviathan, also of the Damocles Anthology).
Also, I recommend ignoring any and all stories written by Phil Kelly because he has an awful record
. This recommendation even stands for the Farsight Enclaves Supplement, as the story was written completely by him and it is full of plot holes and nonsensical narrative.
Last - Ignore that Kakapo42 behind the curtain!
I appreciate the shameless plugs he's giving us all in the Into Silence series, but read the canonical works first. Then you can peruse our stuff at your leisure.
I also agree with TauMan
about reading some official lore (codices for certain) before delving into all of the fanfiction here. Different players have varying tastes and perspectives on what they like about the Tau or how they're portrayed. Even my recommendations above are a result of cherry-picking the stories that cater to my own sensibilities regarding the Tau. The extreme ends of this spectrum are: "Noblebright" Tau which are truly good and thematically out of sync with the universe, and "Grimdark" Tau which are a dystopian Big Brother meritocracy held together only by psychic pheromones from the Ethereals (other minor differences of opinion exist in the fandom, such as XV8s being piloted like aircraft or like a Landmate
You can find more stories and articles in the Card Catalog
. It's a bit outdated by now, but it has the inaugural stories as well as most up to the release of 6th edition. Also, the Library features not only fan stories, but it often has a few reviews of official stories, and some rather in-depth discussions about multiple topics across the fiction. Seeing such discussions might help inform you as to what "brand" of Tau you prefer, and what stories might cater to it.