If you are new to elderberry, welcome! There's more to read in "Part 1" of Elderberry Lore - and great information here in "Part 2." While elderberry (Sambucus nigra spp. canadensis) gets a lot of attention in the winter time, there are plenty of ways to use it all year round.
Our ancestors used the branches to make blow pipes and whistles because of the soft heart-wood, and in some cultures elder plants were called 'the tree of music'. We don't recommend that anymore because of the glycosides (cyanide) in the branches, roots, and leaves. One enterprising man (probably French) set up a pub in England, naming it Pontack and soon his elderberry 'ketchup' was known by that name, too. Elderflower is known to be good for the skin, and can be made into a homemade facial spritzer.
In Europe, one was advised never to rest under an elder bush during midsummer, or one would fall asleep never to wake up again! It was also said that the Elder Mother, who lived in the bushes, needed to give permission before cutting one down. But if you asked, she would protect you. And that fairies lived in the branches. I haven't seen the fairies, but the insects adore the pollen-laden flowers. The birds (usually cat birds) devour the berries, and the rabbits appreciate the bushy cover when being chased. We often find birds nests wedged in the branches after the leaves fall off in late autumn.
I love spotting Sambucus bushes in June, when their white-cluster flowers are blooming here in Connecticut. They prefer moist soil, I often see them near culverts and gulleys along the roads. (If you go elderberry-hunting, don't assume the bush is edible, though, several varieties are toxic. Ask a smart local gardener/plant guru first, or consult an authoritative guide or book.)
Elderberry bushes are fairly easy to grow. In fact if they are in suitable surroundings, they will take over the area. They grow best from "cuttings", available in the late winter when elderberry farmers are pruning their bushes. We start ours in potting soil and give the little sticks lots of water, transplanting them into larger pots, and eventually the soil outside. Then we wait for the insects, birds, and small creatures (or fairies!) to take up residence.