Astrology and Horoscope Homepage - Astrodienst - the premier astrology site - includes Free Astrology and Horoscopes, My Astro, Personal Daily Horoscope, Extended Chart Selection, Horoscope Drawings & Calculations, Horoscopes by Liz Greene (among the foremost contremporary astrology authors), and much more. An excellent site both for the beginner and for experienced astrologers.
Wikipedia - Astrology Portal
Astrology - a good introduction to Western Astrology, in the context of W.B. Yeats' occult researches
Always Astrology com - friendly how-to intro to Western Astrology
Astrology - Jyotish - The Vedic Astrology of Lanka India Nepal and Tibet - a large site with lots of information, obviously marketted to thw newspaper horoscope type reader, rather garish with all those animated gifs, but has a lot of information not found on Western astrology sites.
The Problem of Astrology by Robert Schmidt
Astrologia - soul centered astrology