As Holly told you, google "Learn chinese free" and you can get a lot of resources.
I would like to suggest you to learn Manderin also, the official spoken language used in China. It is because Manderin is easier to learn compare to other spoken languages in China. Although each Chinese word is pronounced very differently in different regions in China, I think many Chinese people know Manderin.
As for Chinese words or Chinese characters, there are two versions as well. They are the simplified Chinese characters and the traditional Chinese characters. Simplified Chinese is widely used in mainland China and traditional Chinese is widely used in Hong Kong and in Tai Wan. The structures of traditional Chinese characters are more complicated then the simplified ones. However, even if you can read traditional Chinese characters, it doens't mean you can read simplified chinese characters as well. So I think for starters, you can choose either one to learn but you must stick to it and don't shift from the simplifed version to traditional version or the other way round too often. In fact, many chinese characters in these two version are the same, so you don't have to worry too much about which version to choose.
By the way, I'm from Hong Kong, China and I speak Cantonese (I don't speak Manderin well). However, don't expect too much help from me as I'm always VERY busy. Also, I may not be able to continue posting in this thread in this month because I have a lot of things to do.

Perhaps in May, I'll have more time.