Last week I asked a question about live username availability. Paul Wilkins gave me some useful links which I have working now, But at the same time I still need to check if no fields are empty when the form is submitted and I am realy struggling to make this work. I have been looking for tutorials and/or examples of a combination of those two (Form Validation and Live email check) but couldn't find any. So what I basically need is a function for three fields (name, username and password). None of the fields should be empty and the email field should be checked against values from the database!

Does anyone know of a good example or tutorial where those 2 functionalities are combined.

Thank you in advance!