Bible Dictionaries and Encyclopedias are basically the same thing. The both present articles that are related to the cultural, historical elements of the Bible. There are articles about people, places, events and customs. Some articles/entries may include a bibliography for further research.
Most of the Dictionaries and Encyclopedias will be found downstairs in the reference section of the Library.
Many of these IVP Dictionaries are available as a searchable eBook within our Credo Digital Reference. This link is to the page to pick which of the Dictionaries you would like to use.