The .NET XML Schema Definition Tool can be used to generate classes from any XSD and can be used in conjunction with the XML Serializer to do what's described.
The Selling On Amazon Guide to XML (SOA-GuideToXML.pdf) does not contain references to the correct XSDs. The links are inconsistent with the XSDs that are reprinted in the document. My old link to correct XSDs is no longer valid. My best guess is that they can be found here (requires a Seller Central login).
This (very long) command will generate all the needed classes so far as I know. Note that you will need to make some minor changes in the generated file. I don't remember which way it worked, but I either needed to change certain 2-D arrays to 1-D arrays ([][] to []) or vice-versa. I remember the places where I had to make these changes being fairly obvious:
xsd xsd\amzn-base.xsd xsd\amzn-envelope.xsd xsd\amzn-header.xsd xsd\AttributeGroups.xsd xsd\AutoAccessory.xsd xsd\Beauty.xsd xsd\CameraPhoto.xsd xsd\CatPIL.xsd xsd\CE.xsd xsd\ClothingAccessories.xsd xsd\Customer.xsd xsd\CustomerAddress.xsd xsd\FoodAndBeverages.xsd xsd\FulfillmentCenter.xsd xsd\FulfillmentOrderCancellationRequest.xsd xsd\FulfillmentOrderRequest.xsd xsd\Gourmet.xsd xsd\Health.xsd xsd\Home.xsd xsd\HomeImprovement.xsd xsd\Image.xsd xsd\Inventory.xsd xsd\Item.xsd xsd\Jewelry.xsd xsd\Lighting.xsd xsd\Listings.xsd xsd\ListingSummary.xsd xsd\Loyalty.xsd xsd\MerchantListingsReport.xsd xsd\Miscellaneous.xsd xsd\MultiChannelOrderReport.xsd xsd\Music.xsd xsd\MusicalInstruments.xsd xsd\NavigationReport.xsd xsd\Offer.xsd xsd\Office.xsd xsd\OrderAcknowledgement.xsd xsd\OrderAdjustment.xsd xsd\OrderFulfillment.xsd xsd\OrderNotificationReport.xsd xsd\OrderReport.xsd xsd\Override.xsd xsd\PaymentMethod.xsd xsd\PetSupplies.xsd xsd\Price.xsd xsd\ProcessingReport.xsd xsd\Product.xsd xsd\ProductAttributes.xsd xsd\ProductClothing.xsd xsd\ProductImage.xsd xsd\Relationship.xsd xsd\ReverseFeed.xsd xsd\SettlementReport.xsd xsd\Sports.xsd xsd\Store.xsd xsd\SWVG.xsd xsd\TiresAndWheels.xsd xsd\Tools.xsd xsd\ToysBaby.xsd xsd\TypeDefinitions.xsd xsd\Video.xsd xsd\WebstoreItem.xsd xsd\Wireless.xsd /c /n:WebLinc.Services.Amazon.Marketplace > output.txt 2>&1
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