encyclopedia article from Britannica.com
Another hyperlinked article, this one a bit more thorough. Contains imbedded links as well as organized links of related topics.
Genealogies and Family Trees
From Encyclopedia Mythica
Greek Mythology Gods
Adapted from Edith Hamilton. This page is a hyperlinked genealogy of the major gods.
Family Tree of Greek Gods and Goddesses
From the University of Michigan, a nice hyperlinked family tree of both Greek and Roman gods. If you are interested they also have trees for Norse gods.
The McGraw-Hill Companies, Inc..