Unfortunately, even if you code a contact form into your site (instead of visible email address)
with a captcha image (the thing where you have to type in matching letters or do a math sum) you'll stlll get spam - if you've only gotten one or two these past few months you're really doing OK

Just redo the encoding....
It's kind of unavoidable, sadly...
Another suggestion is to use a different email on your site than you do for any of your other business communications - and yet a third to sign up for newsletters, etc. That way your spam will tend to be central to the non-client useable email addresses.