Let me comment first on the text. That's one of the most misunderstood texts in the Bible, part of the problem being the Elizabethan English that's found in the old King James Version. The other part of the problem is in translation from the Hebrew. The Hebrew has about seven distinctive words that can be translated by the English word evil. There are all different kinds of evil. There's moral evil. There's what we would call metaphysical evil—finitude, for example. Whenever the Bible speaks of God bringing evil upon people, it is evil from their perspective. When the fires fell upon Sodom and Gomorrah, the people did not look upon that as a good thing. That was bad news. But it was ultimately good because it was an expression of God's judgment upon their wickedness. It was a punishment wrought by the hand of God upon evil. That doesn't mean that God did something wrong or something morally evil by visiting them with judgment.
This Isaiah text is also written in poetic form. It uses parallelism, a pattern of poetry common to Old Testament Judaism. There are even different types of parallelism.
An example occurs in the Lord's Prayer when Jesus says, "Lead us not into temptation, but deliver us from evil." Those two thoughts are parallel and they're basically synonymous; they are saying the same thing only with different words. We find that often in the Psalms.
In Isaiah 45 we have an example of two statements next to each other that are antithetical parallelisms. The first verse is "I create the light and the darkness." Light and darkness are opposites; they're contrasts, they are an antithesis one to another. That's why it's called antithetical parallelism.
The next statement has the same kind of antithesis, but how is the wording? "I make peace, I create evil." It doesn't ring true because peace and evil in our vocabulary are not antonyms, are they? Whereas light and dark are opposites, these are not. What the text is saying is that as God brings good things to bear in this world, he also brings about calamities in his judgment. It is not speaking about the original creation. It's unfortunate that that language persists in that particular translation.
Now, why did he create Lucifer? I don't know, but Lucifer was not created evil. We have to remember that Lucifer was created as an angel—who later rebelled against heaven.