In most cases, registering for a GST account is only necessary when your sales reach $30K in a year (technically four quarters, not a calendar year). When you file your tax return, you'll just use your name and address as the name and address for the business if you don't have a Business Number.

If you are selling your products to the US, I'd advise checking into any additional business registrations needed. Etsy should have plenty of resources for you on this subject. Good luck with your new business!