At it's simplest, GreenPlantSwap is a great place to buy good plants grown locally. Simply check out the growers near you in Local to Me after sign up or log in and, when you find what you are looking for, send them a plant request or send them a general message from their Grower page.
It is usually best to propose a visit to view, pay and collect the plants. If you then find other plants of interest when there, so much the better. That's all part of the pleasure in swapping plants with other interested gardeners.
You are also free to invite them back to your garden if you think you have something that may interest them.
Buying longer distance
You will not always find the plants you want near you. Quite a number of our Growers, however, are willing to courier plants to you if you cover the cost. Those that do, indicate how on their Grower page under 'Delivery terms'. You will also see a little 'lorry' symbol on their listings where this is offered.