I think if you ask your pastor, you will find that what I'm about to say is true and that he has probably had the same of a similar experiance.
I have had more than one person come to me seeking information about Jesus with these words, or something close to them:
"Pastor, I just read a book by .... concerning the end times, can you help me understand..."
Now the words may not be exact, but the sentiment is, the books written by Hal and others, esspecially the left behind series, have gotten more than one to come seeking a saving knowledge of the Lord.
Is it good that they make a profit of these books? I can't answer that, but, I for one would rather see a man make a living by selling his books than going around giving them away and begging money.
Alas