Inside the Spend Bitcoins Merchant Center you will be able to list your business and list your products to be easily found by the millions of users in the bitcoin economy.
You can enter products, either manually or upload your already existing product feeds from formats provided by Google, Amazon, Pricegrabber, CSV documents and more.

The beauty with bitcoin is that you can choose to start accepting it free today without asking anyone permission. Just choose a wallet at https://bitcoin.org/en/choose-your-wallet, slap a bitcoin accepted banner (some free ones at https://en.bitcoin.it/wiki/Promotional_graphics) on your site, and ask people who want to pay in bitcoin to ask you for a bitcoin invoice from you.

If you have a big store or this all seems tedious to you, there are established companies that will do all the work for you:

Option 1: Set up shop at Shopify. They will integrate bitcoin payments into your shop through bitpay or coinbase.

Option 2: Integrate bitpay or coinbase into your own site. Both allow you to either accept bitcoins directly or to accept bitcoins as a form of payment that is then deposited to your bank account in your local currency. Both have fees far lower than credit or debit cards!

If you are new to online commerce or you are smart enough to know you can always use more training, see SpendBitcoins founder Jeremy West's personal endorsement of Wealthy Affiliate University here.