Answers for 21-40! It really gets difficult now!
21: Elrohir
22: Elfhelm
23: Elladan
24: Eomer
25: Erestor
26: Erkenbrand
27: Faramir
28: Ferny
29: Fredegar
30: Gloin
31: Glorfindel
32: Theoden
33: Theodred
34: Thranduil
36: Grima
37: Grishnackh
38: Gwaihir
39: Halbarad
40: Haldir
More coming soon!