It depends on whether you are submitting the form normally or via an AJAX call. You can find lots of information at jquery.com, including documentation with examples. For submitting a form normally, check out the submit() method to at that site. For AJAX, there are many different possibilities, though you probably want to use either the ajax() or post() methods. Note that post() is really just a convenient way to call the ajax() method with a simplified, and limited, interface.

A critical resource, one I use every day, that you should bookmark is How jQuery Works. It has tutorials on using jQuery and the left-hand navigation gives access to all of the documentation.

Examples:

Normal

$('form#myForm').submit();

AJAX

$('input#submitButton').click( function() {
    $.post( 'some-url', $('form#myForm').serialize(), function(data) {
         // ... do something with response from server
       },
       'json' // I expect a JSON response
    );
});

$('input#submitButton').click( function() {
    $.ajax({
        url: 'some-url',
        type: 'post',
        dataType: 'json',
        data: $('form#myForm').serialize(),
        success: function(data) {
                   // ... do something with the data...
                 }
    });
});

Note that the ajax() and post() methods above are equivalent. There are additional parameters you can add to the ajax() request to handle errors, etc.