Are there any other books, divined by God, regarding Christianity? To my understanding, the bible is divinely inspired by God? However is this the only book that has been inspired or developed through this method? Are there other books equivalent or near equal to the bible in regards to Christianity?
Prerequisite: Before giving a straight answer, we need to deal with the canonization of the Bible which is a subject of endless debate. Therefore, let us assume that the Bible in this context means the complete Bible including the Apocryphal Books as well.

Are there other books equivalent or nearly equal to the bible in regards to Christianity?


Answer: Yes!. 

There are some books nearly equivalent to the books in New Testament Canon but not equal.

Epistles of Clement:
This epistle was included in many of the oldest surviving copies of NT.

Epistle of Barnabas:
Very important epistle written by Barnabas who was a companion of Saint Paul. 

The Shepherd of Hermas: Less important but found in many old codices.

Dialogue with Trypho:
A good book which defends the early Christian Faith and theology. Trinity concept is well explained here.

Didache:
A book which explains the ordinances of the early Christian church. Method of Baptism is well described.

Still there are some authentic books which are of far less importance, written by the Church Fathers, but I don't think they are worth mentioning. 

Conclusion: As mentioned, these books are not equivalent to the NT Canons but are very close. There is no need of reading them because they speak the same thing what the Canons are saying. They are useful only to defend the authenticity of the NT Canons and to know the early Christian Faith.

Note: Only the NT Canons are regarded as Divinely Inspired by God. Other books like the ones mentioned here may or may not be inspired by God. Even, how the Book of Revelation was selected instead of The Apocalypse of Peter in the NT Canon is also something which we don't really understand.