Figure out the missing letters to complete the first four lines of a famous poem by an equally famous Romantic Poet. Then arrange the letters to form two words- one: the title of the poem. Another: the surname of the poet by which he is most referred to. So get started!

I ANDEED lonely as a clou hat loats on hig o'er vale and hils, hen ll at nce I aw a cod,
A hst, f golen afodls;