The Houghton Library blog just announced its November digitizations, including three books of Blake:

Blake, William, 1757-1827.
The book of Thel.
Visions of the daughters of Albion.
[Lambeth] : The author & printer Willm. Blake, 1789.
Lowell EC75.B5815.793va

Songs of innocence and of experience shewing the two contrary states of the human soul.
[London] : The author & printer W. Blake, [1789-1794]
HEW 1.4.4
Printed and hand-colored by the author, three of Blake’s greatest and most beautiful illustrated works.

They’re definitely worth a look! Shots include full pages, cover, and book plates. You can read about the other books and manuscripts digitized this month here.