Contact your local or statewide Agricultural and Natural Resources department (click on the link in the Resources section below), to find out which species of wild blackberry bushes will make good candidates for your area and are not considered an invasive pest.
Contact your local nurseries or home and garden centers to see if they carry any wild blackberry bushes. If they do carry wild blackberry bushes, you might find that they only carry them during the right season in your area for planting. Get the information on when the nursery carries the wild blackberry bushes and mark the shopping date on a calendar.
If the local nursery and garden centers do not carry wild blackberry bushes at all, search through newspaper ads or using the Internet to see if there is a native plant nursery or an edible plant nursery in your city, county, or state. Usually plants sold locally, or in the same zone, or in your state will adjust easier.
Try finding the wild blackberry bushes you desire by posting a wanted ad on a gardening forum. Garden sites that provide forums like organicgardening.com, davesgarden.com, backyardchickens.com have areas for plant exchange and seed swapping. Some websites offer a virtual bulletin board where you can post a wanted ad or find another gardener willing to sell and ship their wild blackberry bushes to you.
Consider purchasing cuttings if you are planting a large area with wild blackberry bushes to reduce your costs. Many times cuttings are more affordable than large blackberry bushes as well as easier to handle when transporting and planting. However, cuttings might not bud or produce berries for one or two years.