How to add a form in wordpress using wordpress predefined functions

I'm using wordpress 3.0.1 and using stheme.i 开发者_高级运维want to add a new form below the comment form with some fields like name,email,phone.no,etc.how to add a new fields using wordpress functions.for eg.in comment form there is a predefined functions like get_approved_comments,get_comment,comment_field etc.Is there any functions in wordpress to create a custom form with some author defined fields or how to create a form with some fields.

I think what your are looking for is comment meta. See this post. It has a practical example on the topic.