Historical or legendary druids

Amergin Glúingel
Bec mac Dé
Bodhmall -- female druid in the Fenian cycle
Cathbad --- Ulster cycle
Gwenc'hlan -- 6th century Breton
Merlin --from the Arthurian legends
Mug Ruith -- blind druid in Irish mythology
Tadg mac Nuadat -- Fenian cycle
Tlachtga -- daughter of Mug Ruith
Diviciacus or Divitiacus of the Aedui is the only druid from antiquity whose existence is attested by name.

Modern druids or neo-druids

Getafix, a Gaulish druid appearing in the French comic series The Adventures of Asterix sometimes translated as Panoramix.
Merlin, a wizard who appears in Arthurian legend and is presented as a druid in some modern works, including The Warlord Chronicles series of books by Bernard Cornwell and the 2004 film King Arthur.
Taliesin, a powerful druid and the penultimate "Merlin" of Britain in the Mists of Avalon novel by Marion Zimmer-Bradley
Allanon, one of the main protagonists in the Shannara series by author Terry Brooks.
Pikel Bouldershoulder, in the novels of The Cleric Quintet series by R.A. Salvatore.
Amergin, bard in the novel Bard, by Morgan Llywelyn, and his brother Colptha, a diviner.
Atticus O'Sullivan, real name Siodhachan O Suileabhain, last of the Druids in the The Iron Druid Chronicles series.
Kevin, druid, harpist and last "Merlin" of Britain, in the Mists of Avalon novel by Marion Zimmer-Bradley