XML to CSV Data Merge and Conversion

I have a supplier with product information stored in four different locations. This is a project to set up a system to merge that information into a single CSV file, on a daily basis. The first thing that we have is a link to a zip file, that has 24 xml documents, which contain the descriptions of the products in the catalog. This file is updated once a month. This file references a categories file, that has category information. This is also updated once a month. Then we have a link to a zip file containing 24 xml documents, which pertain to in stock, out of stock, and which also contains additional product information. This is updated on a weekly basis, and contains the entire catalog of products. If a product is missing from that file it means it has been discontinued. Finally we have a link to more zipped files, which are updated twice a day, with daily stock change and quantity amounts. We need a system that merges the information from all of these different files into a single csv file. We also need to be able to append information to that file, which will permanently remain affixed to individual products. Example of Descriptions XML <part> <warehouseloc>1-55-AL-1 </warehouseloc> <trackingnumber>435297</trackingnumber> <partnumber>FW114272SM</partnumber> <name>Sample Item Name</name> <imagename>FW133372</imagename> <origincountry>CHINA</origincountry> <Shipping_Method>Ground Or Air Service</Shipping_Method> <weight>1.19</weight> <length>16.00</length> <width>11.00</width> <height>3.00</height> <catalog_desc>2001 CATALOG # 35</catalog_desc> <catalog_page>293</catalog_page> <price>16.80</price> <category1>Child</category1> <category2>4-6</category2> <web_category1>7</web_category1> <web_category2>3</web_category2> <web_category3>4</web_category3> <web_category4>1</web_category4> <gtin>555666777</gtin> <Description>A lovely sample item to wear around the home </Description> </part> The other XML files are similar, with different informational elements. All information is delivered via static links to zipped xml files. The output CSV doesn't have to be anything fancy, just rows of information layed out in appropriate order. Let me know if you have any questions about this project. Thank you very much.