The WHOIS for darknetdesigns dot com is private and lists only the domain host, enom, as registrar. The 877 number cannot be traced to an address.
Domain Name: DARKNETDESIGNS.COM
Registrar: ENOM, INC.
Whois Server: whois.enom.com
Referral URL: http://www.enom.com
Name Server: NS1.IONCODING.COM
Name Server: NS2.IONCODING.COM
Updated Date: 02-nov-2010
Creation Date: 29-oct-2008
Expiration Date: 29-oct-2011
If you have been defrauded or there's been a failure to deliver you should definately contact your cc company to report. Don't know if you're out of time to make a claim but it is likely the only way you'll ever get your money. The net is a very insular place and the payment trail is the only way you'll track this guy down.
Memphis, if you have the name that shows up on your cc statement it may help tracking him, not likely through if it is truly a scam, he will have insulated all public data.