You may not be aware that placing your email address on your "contact us" page is a sure-fire way to get yourself truckloads of spam. As we speak, there are bots traversing the web, looking for email addresses that have been published publicly on web pages. These email addresses (and items that resemble email addresses) are stored and sold to spammers.
So how do you avoid this?
The trick is to display your email in a way that the user viewing the site sees the email address and can click it or copy it into their email program, while robots only see a jumble of characters that to a machine does not look like an email address.
There are a number of sites to help you. My favorite is David Grayson's Email Hider: http://www.davidegrayson.com/emailhider/
What it will do is replace some characters with HTML entities, which are readable by your browser and will display as normal characters. The probability that a character in your email will be replaced is determined by the second number. The closer it is to 1, the more characters will be replaced. 0.6 is a good balance.
There are other sites, too. You can find them using a search for "email obfuscator".
I don't recommend making an image of your email address because then your visitors will have to copy it visually and try not to make mistakes, which is common in long email addresses or noisy images where your email address does not appear clearly.
An Extra Note
Avoid using certain email addresses with your domain. Very common addresses like info@yourdomain, webmaster@yourdomain, and sales@yourdomain are already built-in to spam lists. It's better to use something friendly but also less common. Let's get original and creative, yes?
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