learning chinese on-line resources

Of course, a dictionary is the most basic resource you will need.
Chinese writing is made up of ideograms, instead of latin characters. For this reason, chinese dictionaries should provide a mean to look for a given ideogram. Both of the chinese dictionaries above have applets that allow you to draw with the mouse the ideogram you are searching, and present you with a set of possible characters to choose the right one.
Besides, both dictionaries allow you to search by entering the pinyin transcription (phonetic writing of chinese ideograms in latin characters) of the ideogram(s).

Once you are acquainted with the most basic knowledge about the structure and grammar of the chinese language, your will most likely start looking for chinese texts to translate.
tonghua (fairy tale kingdom) is a charming site full of chinese and western fairy tales. If you try first the most well-known fairy tales of your childhood, you will have te advantage of knowing in advance what you are going to read

Sooner or later, you will want to write chinese texts in your computer. It is likely that the text processor of your choice has built-in support for asian characters, but the default unicode fonts available are usually designed to be readable at small font sizes, and therefore use straight horizontal and vertical lines. If you prefer a nicer font, you can find many free chinese (both traditional and simplified) at wazu. Have a look !

Now you've got the basic pieces to start learning chinese. You have read that the average chinese people learn about 3000 ideograms, but where to start ?. Jun Da is a great site that allows you to list the most frequently used bigrams (sequences of two ideograms) in two sets of chinese texts: The "news corpus" and the "general fiction corpus". Most chinese words are bigrams, so in my view it is better to try and learn bigrams than single ideograms. Depending on your interests, you can choose to list the most frequent, let's say, hundred words (bigrams) on one of the aforementioned corpuses, and try to learn them by heart.

How can you expect to learn a language without ever listening to it ?. But good online sources of listening material are scarce. One of my favourites is Radio Beijing Corporation. There you can choose from a wide range of online radio broadcasts, covering news, sports, culture, etc. Among them, the one I like most is CFM1051, dedicated to the reading of books by professional readers. They general speak in a clear and slow voice, that makes this radio broadcast specially suited to the purpose of learning mandaring.