Each Saleae logic analyzer comes complete with the accessories needed—wire harnesses, clips, a USB cable, and a carry case.
However, if you would like to purchase additional accessories, you can find the complete listing here: https://www.saleae.com/accessories
Please note that items marked "Gen 2" are designed to be used with the new Saleae devices—Logic 4, Logic 8, Logic Pro 8, and Logic Pro 16. The items marked "Gen 1" are for the now discontinued products—original Logic and Logic 16.
Generally, extra accessories will make it easier to switch between different projects or integrate the logic analyzer into a custom design.