Sri Ramana Maharshi:

http://www.ramana-maharshi.org/fullbook.htm

---

Sri Swami Sivananda Saraswati (Divine Life Society):

http://www.sivanandadlshq.org/download/download.htm

(Hinduism, autobiography, worship, Bhagavad Gita, God exists, Jesus, Mind, parables, dreams, yoga, celibacy, vedanta, what happens to the soul after death etc. - EXCELLENT SITE)

---

Bhagavan Nityananda:

In Divine Presence
Swami Chetanananda and M.U. Hatengdi. Rudra Press
P.O. Box 13390 Portland, Oregon 97213
Editor, Cheryl Berling Rosen

The Sky of The Heart: Jewels of Wisdom From Nityananda
compiled and translated by M.U. Hatengdi and Swami
Chetanananda; Rudra Press P.O. Box 13390 Portland, Oregon 97213.
Editor, Cheryl Berling Rosen

The Chidakash Gita
 

---

Sri Chandrasekharendra Saraswathi Mahaswamiji
(Shri Kanchi Kamakoti Peetham)

http://www.kamakoti.org/newlayout/sitemap.html

(Hindu Dharma is a book by the swamiji which has complete information on Hinduism. Just scroll down this page. The swamiji is the 68th acharya of the Adi Shankaracharya lineage)

---

Sri Paramahansa Yogananda (SRF):

http://www.crystalclarity.com/yogananda/

(Autobiography of a Yogi - recommended book)

---

AC Bhaktivedanta Swami Prabhupada (ISKCON):

http://harekrishnatemple.com/modules.php?name=Downloads&d_op=viewdownload&c id=3

(Bhagavad Gita, Krsna book, Bhagavatam, after death. The author is the founder-acharya of the Hare Krishna movement, descending in the lineage of Sri Chaitanya.)

---

Sri Swami Vivekananda:

http://www.hindunet.org/vivekananda/

(incomplete - just some texts of speeches, quotes and short writings. The author is the disciple of Sri Ramakrishna Paramahamsa.)

---

Paramahamsa Omkarananda Saraswati:

http://www.omkarananda-ashram.net/Online_en.html

---