Ares Specific Resources:
Neos Alexandria: http://neosalexandria.org/the-pantheon/ares/
This short page shows how Ares fits into the pantheon of the group Neos Alexandria. It contains a short list of epithets, offerings, and prayers by members.
Another shorter page, this page gives a description of how Ares fits into the Hellenic system, including the Homeric and Orphic hymns. So far, this is also the only site I know of that goes into Orphic theology. The second link contains a video of a hymn to Ares.
Operated by Hellenion, this page details their practices regarding the god. It has original prayers, shrine photos, and offering advice.
Sacred Texts: http://www.sacred-texts.com/wmn/rca/rca06.htm
This is an excerpt describing the cult of Ares among the Amazons. and should be especially helpful for reconstructing this cult.
The Immortals: http://messagenetcommresearch.com/myths/bios/ares.html
This small page contains the book and line for each reference to Ares in both the Iliad and Odyssey.