Alrighties :D
www.feritradition.org : The main site. Lots of interesting stuff. The Grimoire section contains a lot of basic information on Feri, though you should keep in mind that specific practices differ from line to line and coven to coven and even practitioner to practitioner.
http://www.feritradition.org/witcheye/webindex.html is the real gem, IMO. Many of the essays are Feri-specific, but some are good reads regardless of whether or not you identify with Feri at all. And the poems are really nice, as well.