The Finding API can be used in conjunction with any of the eBay APIs. We recommend you try using the Finding API together with one or more of the following APIs.
eBay Shopping API
The Shopping API can be used to augment the Finding API to create a rich buy-side application. The Shopping API provides calls to search for products, user info, and active listings. It also provides data that can be used by the Finding API. For example, you can use FindProducts to retrieve the eBay Product Reference ID for use as input for the findItemsByProduct call, or use GetCategoryInfo to retrieve the eBay category ID numbers for use with findItemsByCategory.
See the Shopping API User Guide and Shopping API Reference for more information.
eBay Trading API
The Trading API offers authenticated access to eBay data. Much of the Trading API is geared toward helping sellers list items, retrieve inventory and sales data, manage post-transaction fulfillment, and accessing private user information such as My eBay and Feedback details. If you are familiar with the Trading API, it can be used to retrieve additional details about users, items, or categories. For example, the GetCategoryFeatures call in the Trading API can help you to programmatically download details about the supported condition IDs per category and site
See the Trading API User Guide and eBay Trading API Reference for more information.