Sounds like a fun project. :) I would be happy to do this for you. For this project I would use Perl with mySQL (because of Perl's excellent parsing and XML capabilities). Note that the requests to Amazon would have to be spread out over a day or so (they may ban your account if you make more than one request per second). My price includes this functionality. I've also put some other suggestions in the PMB. Look forward to working with you!