Lots of people know their sun signs (Libra, Capricorn, Leo, etc) but are always surprised to find out that there's much more to astrology than that.
http://www.astro.com/cgi/ade.cgi?ract=ahor.cgi&
If you know your time and place of birth, you can plug it into here to get your full natal chart--where ALL of the planets were in the Zodiac when you were born, not just the sun. If you don't know your time of birth, just put in 12 noon. The planets will be right, but the house placement will probably be wrong (unless you were born around 12 noon =P)
You'll get something that looks like this:

So my sun is in Cancer, but my moon and ascendant (the first house of the twelve houses, the one that is about how you interact with the world and your personality) are in Pisces.
Astro.com also has a nice "clickable portrait" option that you can find right on the front page, which will give you some basic cookbook definitions and explanations of certain aspects.
Some from my chart:
The Sun square the Ascendant indicates that when you express yourself you unknowingly cause others to react strongly. You come on a bit strong, which just doesn't set quite right with people, and they may find this behavior overbearing.
...
If you realize that it is not your creative abilities but your attitude that sometimes offends people, you will succeed in winning complete approval for your competence.
Because of your sense of values, you strive to enrich the lives of others by sharing your good fortune with them.
Your well-developed sense of harmony and appreciation of beauty may be expressed through the arts, music, design, or drama. You radiate warmth in everything you do and are rarely negative in your social contacts.
Other good resources include the astrology and astrology_2 communities on LiveJournal and www.cafeastrology.com.
http://www.astro.com/cgi/ade.cgi?ract=ahor.cgi&
If you know your time and place of birth, you can plug it into here to get your full natal chart--where ALL of the planets were in the Zodiac when you were born, not just the sun. If you don't know your time of birth, just put in 12 noon. The planets will be right, but the house placement will probably be wrong (unless you were born around 12 noon =P)
You'll get something that looks like this:

So my sun is in Cancer, but my moon and ascendant (the first house of the twelve houses, the one that is about how you interact with the world and your personality) are in Pisces.
Astro.com also has a nice "clickable portrait" option that you can find right on the front page, which will give you some basic cookbook definitions and explanations of certain aspects.
Some from my chart:
Sun square Ascendant
The Sun square the Ascendant indicates that when you express yourself you unknowingly cause others to react strongly. You come on a bit strong, which just doesn't set quite right with people, and they may find this behavior overbearing.
...
If you realize that it is not your creative abilities but your attitude that sometimes offends people, you will succeed in winning complete approval for your competence.
Venus trine Uranus
Because of your sense of values, you strive to enrich the lives of others by sharing your good fortune with them.
Your well-developed sense of harmony and appreciation of beauty may be expressed through the arts, music, design, or drama. You radiate warmth in everything you do and are rarely negative in your social contacts.
Other good resources include the astrology and astrology_2 communities on LiveJournal and www.cafeastrology.com.
