Once you have purchased a wine on Sharewine, you will receive a confirmation on your email. In this email there will be a link from which you can contact the seller. Then you can agree on details about payment and whether the wine should be picked up or sent.
You can also contact the seller by:
1) Click on "My account" in the top right corner.
2) Click on "My purchases".
3) Here you will be able to see the seller's name as well as the icon below. You can click on this, and then you can write a message to the seller and make a deal about delivery or pickup.