Blake's Book of Job can be found in many websites:
Blake Archive, the Gutenberg.org, wikipedia, bc.org, and many others, no doubt. Adelaide University (Australia) provides a picture and an engraving as well.
Job Plate 5 on
The biblical text that Blake included in the engraving:
6] And the LORD said unto Satan, Behold, he is in thine hand; but save his life.
 So went Satan forth from the presence of the LORD, and smote Job with sore boils from the sole of his foot unto his crown.
 And he took him a potsherd to scrape himself withal; and he sat down among the ashes.
 Then said his wife unto him, Dost thou still retain thine integrity? curse God, and die.
 But he said unto her, Thou speakest as one of the foolish women speaketh. What? shall we receive good at the hand of God, and shall we not receive evil? In all this did not Job sin with his lips.
James 5:11 Ye have heard of the patience of Job, and have seen the end of the Lord;
In the image:
Job is despondent, as is his 'God' above. Here he depends on the Letter of the Law, giving alms to 'the poor'. But Satan is full of energy.
This like all the Job pics is represented as the contrast between the inner and outer, between the mundane and the eternal. There is little of the eternal in this picture. We get very little from Blakes Book of Job, or anything else for that matter if we confine ourselves to the literal interpretation.
Here's the picture: