Hello,
Sorry to hear you are receiving spam from your contact page. This is indeed a problem where email addresses are in plain sight on websites. Scrapers and bots find them and harvest them for spamming later on. The best way to decrease this is with a contact form using the captcha, which is what you said. These are generally built with php and connected to an account that allows the captcha block to show to help prevent bots from getting past the form (though some still can.) You can do this by coding it yourself or by hiring a developer to create one for you. If you are one of our website design customers you may be able to contact them to see if they can create one for you.
Kindest Regards,
Scott M