Just call the AA RTW desk in the U.S. (1-800-247-3247), have them set up the ticket, give them a credit card number and have them issue the (electronic) ticket. No need to use a travel agent, who will add absolutely nothing to the process.
sorry for double posting, one more question...
So, I got all the way up to purchasing, and then was told that they couldn't take my Aussie credit card over the phone... Any suggestions? Should I just call back and hope a different agent will process my card?