If I understood you correctly, you need some tool to update your products directly from vendor.
We recommend you to try out Automated Product Import addon of Store Manager for Magento.
Those 2 products in combination can update your products on schedule directly from .csv file provided by your vendor (supplier) and you yourself set time of the update (every hour, day, week or months). Store Manager and Automated Product Import addon are desktop applications, so they will be running locally and without need for you to perform import manually. All that is required from you is to set up import for the first time and then the updates will be make automatically.
Here you can download 14-days free trial version of both Store Manager for Magento and Automated Product Import addon -
If you mean vendor like manufacturer to be specified for your products, please check manufacturer attribute in Default attribute set -> General attribute group. It can be set in bulk as well either using Magento default import or with Store Manager import.
Any details appreciated so I could guide you further.