Of course, number one is my Bible. I almost always use the King James Version -- it's just what I have used since I was a kid. The one I am using now is a KJV study Bible, which has been immensely helpful in my personal devotions.
Bible Gateway
http://www.biblegateway.com/
A wonderful way to look up by passage or search for a phrase.
Nelson's Biblical Cyclopedic Index
Thomas Nelson 1979, 1995, 2010
This is a new one for me, but I have thoroughly enjoyed it so far.
Holman Illustrated Bible Dictionary
I turn to this time after time. Even my teenagers have gotten engrossed in it.
Manners and Customs of Bible Lands
by Fred H. Wright
Moody Press 1953, 1972
This was my grandfather's book. Very interesting to sit and read. Gives lots of information, pointing out the differences between Eastern and Western cultures. Helps with understanding what the Bible is really saying.