Computer-implemented systems and methods for building a database of bales of cotton available for sale, and for electronic commerce of bales of cotton.  A fiber quality measurement instrument located in a cotton gin provides fiber quality data substantially concurrently with the making up of cotton into individual bales.  The fiber quality measurements instrument is connected through a communications network, such as the Internet, for uploading fiber quality data to a database storage device.  For electronic commerce, a search engine is connected via the communications network to interrogate the database to select bales having the fiber qualities within specified ranges for a candidate buyer.