imo london folk scene is one of the worst, Marling is an exception because she reminds me of Joni Mitchell but yeah uhh Chad VanGaalen, Sufjan Stevens, Andrew Bird, Joanna Newsom, A.A. Bondy, Akron/Family, Alela Diane, Annuals, Beck, Bon Iver, Calexico, Iron & Wine, Charge Group, Charlotte Gainsbourg, Devendra Banhart, Dirty Projectors, El Perro Del Mar, Firekites, Fleet Foxes, Jenny Lewis, Laura Veirs, Lisa Mitchell, M. Ward, Monsters of Folk, My Brightest Diamond, My Morning jacket, Okkervil River, Paul Dempsey, She & Him, Silver Jews, Vetiver, Yo la Tengo.
a lot of the bands i mentioned though are more alt folk, alt country, new folk or just plain folk. indie folk is a very broad genre and i guess my definitions of what classifies indie folk is different/wrong, but yeah just pick any, they are all good