Omega Stone - Riddle of the Sphinx II, The

Gameboomers: Omega Stone Walkthrough - http://www.gameboomers.com/wtcheats/pcOo/omegastone.htm
Detailed walkthrough including screenshots of puzzle solutions.

Low-Spoiler Guide to The Omega Stone - http://www.angelfire.com/hero/tjekanefir/omega.htm
Reviews, gameplay hints, and walkthrough.

The Omega Stone: The Sequel To Riddle Of The Sphinx - http://www.theomegastone.com/
Official site offers a demo, game patches, screenshots, and various downloads.

Universal Hint System - http://www.uhs-hints.com/uhsweb/tos.php
Offers specific questions and hints in progressively detailed steps.