Add Captcha, JavaScript Validation, and Capture IP Address to Form

The most popular real estate database online application, Top Producer, offers a webform that clients can put on their own websites that when submitted process directly through to their website and update the client's database. There is no CAPTCHA (word verification) on the forms, and since I do not have access to the processing form, I can't place the CAPTCHA code in their processor. As a result, clients are getting flooded with SPAM. Top Producer recommended that since they don't support their own forms, that I should contract for a JavaScript solution to check for the Word Verification before allowing the form to submit. In addition, I would like to capture the sender's IP address so that in the even that they are manually entering the SPAM, I am able to Deny their IP address. The form is already completed and working. I just need to complete this process. Thank you.