BBL 2011 Understanding the Old Testament: Word Study

Concordances list words in the Bible and tells you every verse which contains that word. Exhaustive concordances list EVERY word, where as selective concordances focus on words and verses considered important by the compiler.

Because Strong's Concordance is no longer under copyright protection, you'll find a number of websites that provide access to it.  Some searches will only give you the Strong's number, others will provide more information, such as the transliteration, and links to other verses using the same Greek or Hebrew word.