I need some Canon EOS advice?

I went into art school majoring in photography ufortunatley the school i go has a very poor photography program so i changed my major. I am still very interested in photography but have just decided to learn on my own but obviously there is a lot to learn. I have an EOS Canon Rebel XS. I am just looking for advice on lenses, flashes and other equipment that I should get to get me started and any helpful tips. I am most interested in portraits and wedding photography and some sports photography. I took a couple classes in college but my knowlege about photography is still very basic. Any advice or guidance is helpful just keep in mind that i am a poor college student!