The LEx platform has a built-in messaging system that allows you to communicate directly with other members of the community. We ask that you always use it for all communications. To message a buyer/seller about a specific transaction you'll need to get to the order details page. To get there, just click on the gear (or your profile) icon to open the main menu, then click on a recent order from the shortlist or View All under Recent Purchases or Recent Sales:

From the order details page, you'll find the Send Message button in the buyer/seller information box:

To message a seller before making a purchase, click the orange Ask the seller a Question button from the listing details page: