goldfish evolution

Question
I own a few goldfish, and I became curious about the origin of goldfish and how they have "evolved" since then. Could you please tell me the origin of goldfish, how it has changed since then, and how it might change in the future. Please answer with personal experience/opinions but if you research the topic, please tell me the source.
Thank you for your attention in this matter.

Answer
Hello Mike,
First of all it's awesome that you are interested in where they came from, other people wouldnt think twice.

The origin of goldfish is from China, And you know all those different species like black moore's fantails, common, koi although i beleive koi is from japan but all those species are basically through force breeding, where they get one species of fish, or a fish that looks like this and a male of another speices or that looks different and they massage the eggs out of the female and milt (sperm) out of the male and put them in a buck together and grow them that way to create a new species.
Although now days different species have been known to breed successfully in aquariums.
I think eventually there will be goldfish made to fit tiny bowls, like goldfish that dont grow if you get me, as many goldfish loose there lives to these bowls, so i reckon they should try lol.

There are a few of the species i dont really like, like the ones with the massive air bags under there eyes, i think its too uncomfortable for them, but i dont own fish like that so...
http://z.about.com/d/freshaquarium/1/0/G/6/goldfish02.jpg