in email forms...
can sum1 please help me on how to create 1 of my clients having a spam prob so i jus wanna add verification code to their email forms. preferbly make it aspx form
please help

Create a bunch of images with funny text in them, and then create a database table linking the URL to the images with the values in them. Then pick a row from the table at random, use a server-side control or response.write statement to show the image, and a text-box for the user to type the solution into. On the submit event, check whether the value the user typed matches the value in your table, and if not, don't let the comment post.

Please have a look at this page http://www.codeproject.com/aspnet/CaptchaImage.asp.
It shows how to make an image on the fly and validate user input.

how about doing this in php or html pages?
i have a imagupload site that id like to add this to and a html contact forum
also how much does this protect from spam??
iv seen many aps that can bypass the captcha like myspace adders etc?

Yeah they can be bypassed but to be honest, as long as youre manipulating the characters (different angles, fonts, sizes etc etc) then its unlikely anyone will try to bypass it unless your site is a very big one.

how would i add this to a existing html or php page?

Youre best of asking in the PHP forum matey, its not hard in .NET so I cant see it being too difficult i PHP either.