Site Updates:

April 1st - added The Narada Purana, The Linga Purana ,
The Padma Purana, and The Siva Samhita.
More to come soon!
Please visit Om Jyotish for a great resource on Jyotish.

Vedas
(links)

Rig Veda
Sama Veda
Yajur Veda
Atharva Veda (incomplete)

Principal Upanishads

Aitareya Upanishad
Brihadaranyaka Upanishad
Chandogya Upanishad
Isa Upanishad
Katha Upanishad
Kaushitaki Upanishad
Kena Upanishad
Maitrayani Upanishad
Mandukya Upanishad
Mundaka Upanishad
Prasna Upanishad
Svetasvatara Upanishad
Taittiriya Upanishad

Gitas

Agastya Gita
Ashtavakra Gita
Avadhuta Gita
Bhagavad Gita
Bharata Gita
Bhikshu Gita
Hamsa Gita
Risabha Gita
Rudra Gita
Sanatkumara Gita
Siddha Gita
Sruti Gita
Uddhava Gita
Uttara Gita
Vasistha Gita

Also see:
Annapurna Upanishad
Maha Upanishad
Tejobindu Upanishad
Varaha Upanishad

Puranas
Brahma Purana
Linga Purana
Narada Purana
Padma Purana

Misc
Hastamalaka

Adhyatma Upanishad
Akshi Upanishad
Amrita Bindu Upanishad
Amrita Nada Upanishad
Annapurna Upanishad
Aruni Upanishad
Atma Upanishad
Atma Bodha Upanishad
Avadhuta Upanishad
Bahvricha Upanishad
Bhikshuka Upanishad
Brahma Upanishad
Garbha Upanishad
Jabala Upanishad
Kaivalya Upanishad
Katharuda Upanishad
Kundika Upanishad
Maha Upanishad
Maha Narayana Upanishad
Maitrayani Upanishad
Maitreya Upanishad
Mantrika Upanishad
Mudgala Upanishad
Muktika Upanishad
Nada Bindu Upanishad
Narada Parivrajaka Upanishad
Niralamba Upanishad
Nirvana Upanishad
Paingala Upanishad
Para-Brahma Upanishad
Paramahamsa Upanishad
Paramahamsa Parivrajaka Upanishad
Sannyasa Upanishad
Sariraka Upanishad
Sarvasara Upanishad
Satyayaniya Upanishad
Savitri Upanishad
Sita Upanishad
Skandha Upanishad
Subala Upanishad
Surya Upanishad
Tejobindu Upanishad
Tripura Upanishad
Turiyatita Upanishad
Vajrasuchika Upanishad
Varaha Upanishad
Yajnavalkya Upanishad
Yogatattva Upanishad

Siva Samhita
Vijnana Bhairava Tantra

Also see:
Amrita Bindu Upanishad
Amrita Nada Upanishad
Kundika Upanishad
Nada Bindu Upanishad
Savitri Upanishad
Sita Upanishad
Siva Sutras
Tripura Upanishad
Uttara Gita
Yogatattva Upanishad

Other Vedantic Texts

Compendiums & Commentaries
Mandukya Karika
Panchadasi
Siddhanta Panjara
Vedantasara

Sutras
Brahma Sutras (best translation)
Brahma Sutras (Unknown tr.)
Narada's Bhakti Sutras
Patanjali's Yoga Sutras
Siva Sutras

Also see
Nirvana Upanishad

Commentaries & Compendiums
Aparokshanubhuti
Atmabodha
Nirguna Manasa Puja
Panchikaranam
Tattva Bodha
Upadesa Sahasri (prose)
Vakya Suddha
Vakya Vritti
Vivekachudamani

Poetic Works
Bhajagovindam
Siddhanta Tattva Vindu

Biography of Shankara
Life Story