Looking Up OT Quotes

When Jesus quotes an OT passage, or for that matter, when any New Testament writer quotes an Old Testament passage, I think it is a good practice to actually go to that passage and read it, reading the whole chapter or the whole book.  Much can be learned from doing this.
1.  We can learn what passages the NT writers keep referring to.
2.  We learn how NT writers and Jesus interpret the OT.
3.  We learn about the context of the passage to which is being quoted.
4.  We see how often OT passages are quoted, let alone alluded to.
5.  We learn where the OT books are in the Bible.
6.  What do you learn?