multilingual websit

hi,
can any one provide me some links from where i can get to know how to develop a multilingual website.
also if some one can give his/her feedback on how to go about it .
actually I want to provide options of changing the content/languge of the page by selecting the desired language option button, as soon as the user clicks that button the content of the page should change to that language.

suggestions are most welcome. !