Railroad ties for landscaping can be found at Lowe's and The Home Depot as well as on the stores' websites. Recycled plastic railroad ties can be found at Wal-Mart and GlobalIndustries.com.
Traditional railroad ties are made out of wood and are often treated with creosote. This allows the pieces to last a very long time in the harshest of climates. However, because they are used, customers should be mindful that the pieces they order may not be the same exact size. Recycled plastic ties offer the appearance of traditional railroad ties and claim to last just as long. Since plastic ties are manufactured, they may fit together better than traditional wooden ties.