Kitab At-Tawheed is one of the best books on the subject of Tawheed (Islamic Monotheism) and ranks high in authenticity. Till date it has gone through various publications; and had been the means for guidance of the millions of people throughout the world; by taking them out of the darkness of polytheism and error.
Author: Muhammad Bin Abdul Wahhab
Publisher: http://www.islambasics.com - Islam Basics Website
A very important book talks about some misconceptions about Islam such as: allowing husbands to beat their wives, punishments by Islam for the criminals, not allowing religious freedom which is considered intolerance, prohibiting music, and terrorism in the name of jihad.
A booklet presented by IPC (Islamic Presentation Committee) to show people who is the Prophet Muhammad (Peace be upon him). It is divided into five sections: introduction, his life, his moral characteristics and mannerisms, his miracles and conclusion.
Publisher: http://www.ipc-kw.net - Islamic Presentation Committee Website - Kuwait
A proof that the Qur'an is from God and that Muhammad is a Messenger of God.
Author: The Memphis Dawah Team
Publisher: Memphis Dawah
Source: http://www.islamhouse.com/p/1283
A Collection Of Wise Sayings (Al-Fawaid): is one of the well-known compilations of Imam Ibn Qayyim Al-Jawziyyah (may Allah have mercy upon him). This book consists of the elevated thoughts that Allah bestows upon some of His servants as He wills. So whenever any of these scattered pearls of wisdom occurred to the Imam, he would immediately record them.
Author: Ibn Qayyim al-Jawziyyah
Publisher: Umm Al-Qura for Translation, Publishing & Distribution
An excellent book for non-Muslims explaining various aspects of Islam.
Author: Pete Seda
Publisher: Islamic Propagation Office in Rabwah
Source: http://www.islamhouse.com/p/1301