I'm not in a position to be able to go and count right now but I think it's roughly 40-50 volumes. I collect antiquarian poetry books so there's not much contemporary stuff. Birthday Letters by Ted Hughes is probably the most recently published volume and the only living poet on my book shelf is Wendy Cope. Mostly its war poetry or other works by war poets, several anthologies from the 1920's, moderns etc. As for pre-20th century stuff it's mostly well known classics- various collected works of romantic poets, Tennyson, Oscar Wilde, Shakespeare, Chaucer, Chapman's Homer... the usual suspects.