It was certainly a pleasant surprise to me to realize that I would no longer have to collect taxes on my art sales as of July 2010. Yes...that sounds crazy, how could a new tax law benefit artists? Simply put, small businesses that collect under $30,000 in revenue a year are exempt from having to collect the HST. The catch is that the very minute that you hit that $30,000 mark, you need to collect taxes on any sales above and beyond. In order to do this properly it is wise to keep track of your sales. The minute that your sales start to creep up to $30,000, march right over to the government offices and sign up to collect HST.
Here is a useful link
http://www.rev.gov.on.ca/en/taxchange/transition.html