From Kodansha:

Vol 1: Kengami no Souryuu / Twin Dragons of Sabertooth
Sting Eucliffe, the White Dragon, and Rogue Cheney, the Shadow Dragon. These two powerful Dragon Slayer wizards are the faces of the Sabertooth guild, but they didn't start out that way - both wizards have been down a road of fantastical adventures and hard-won battles to forge their own way as heroes. Learn how two of the most powerful wizards in Fiore got their start!

Vol 2: Rhodonite / Road Knight
The iron dragonslayer, Gajeel Redfox, has lived his life in the shadows. Even in the motley crew of Fairy Tail, he didn't always fit in. When Gajeel gets news of an escaped prisoner he may be connected to, he must leave on a journey to confront his past. Will he stand strong with his new family in Fairy Tail, or will old forces pull him back into the darkness?

Vol 3: Raigo Issen / Flash of Great Lightning
Following the disbandment of Fairy Tail, Laxus and the Thunder Tribe turn up at the door of Blue Pegasus, seeking to join the guild. Even though they are accepted, the environment is different from Fairy Tail: not only is it a guild, but also a host club. Before they can settle in, Ichiya is kidnapped by the rival guild Red Princess! Laxus and the Thunder Tribe set out to rescue Ichiya from the clutches of a fellow eccentric guild.

**English Translations: **Vol 1, Vol 2, Vol 3