Sparkles Forever I returned an item that was ordered. They did not credit my Visa account or respond to phone calls or emails. Internet

I orded a CZ ring early in June.  The amount of $50.95 was posted June 12, 2010, to my Visa acct. I received the ordered item June 25, 2010.  The ring was too large for my hand so I mailed it back to Sparkles Forever and I had USPS confirmation that the item was received by the company on July 2, 2010.  I asked to either credit my acct. or exchange it for a similar peice of jewelry (spcified).  By July 12th I had not heard anything about the requested credit or exchange.  I called July 12th, July 14th, and July 16.  The answer machine says they will return all calls within 24 hours.  I did not get a call back.  In addition, I emailed the company on July 14th and July 20th.  No answer to either email. 

Their customer service is non existant.  I feel thoroughly ripped off.