You can enter your information here
http://www.astro.com/cgi/ade.cgi?lang=e&am...b266c616e673d65
You might need your birth time, but guessing it to be 12 pm is okay too.
I know most ppl prob don't know about moon signs annd stuff.
Oh, but your sun sign is just what most ppl call your "sign" b/c it's the most commonly known. For instance, your sun sign is virgo as you mentioned.
You know how the sun isn't the only planet in our solar system and thus it isn't the only planet that determines what we supposedly call our astro personality. There are other planets as well. Just imagine the time you were born and all the planets rotating and moving. Your signs corresponds to the position of the planets at the time of your birth.
I guess this is why some mo dooo buddhists ppl asks for your birthday. I've never went to one so I don't know. But I have studies astrology on my own. I know it prob sounds tedious and boring to the normal person.
But just answering your question