The original Japanese novels are published by Tokuma Shoten (徳間書店). Chinese translations are available. Sue Shambaugh has almost finished translating the whole main series into English, and she indicated a publisher may be interested in them...

銀河英雄伝説 Legend of Galactic Heroes
第１巻　黎明編	Book 1: Dawn	11/30/82	translation
第２巻　野望編	Book 2: Ambition	9/30/83	translation
第３巻　雌伏編	Book 3: Hiding	4/30/84	.
第４巻　策謀編	Book 4: The Plot	10/31/84	.
第５巻　風雲編	Book 5: Winds and Clouds	4/30/85	.
第６巻　飛翔編	Book 6: Flying	10/31/85	.
第７巻　怒濤編	Book 7: The Angry Wave	5/31/86	.
第８巻　乱離編	Book 8: Random Separation	1/31/87	.
第９巻　回天編	Book 9: Return to Heaven	5/31/87	.
第10巻　落日編	Book 10: Sunset	11/15/87	.

銀河英雄伝説外伝 Legend of Galactic Heroes Side Story
第１巻　星を砕く者	Book 1: Star Breaker	4/30/86	.
第２巻　ユリアンのイゼルローン日記	Book 2: Julian's Iserlohn Diary	3/31/87	.
第３巻　千億の星、千億の光	Book 3: A Hundred Billion Stars, A Hundred Billion Lights	3/31/88	.
第４巻　螺旋迷宮	Book 4: The Spiral Maze	7/31/89	.