A great book which explains the real beauty of Islam, by Dr Naji Ibrahim Arfaj.
Author: Naji Ibrahim al-Arfaj
Publisher: http://www.abctruth.net - ABC Truth Website
This book talks about the life story of Muhammad, may Allah exalt his mention, and his beautiful manners. It also brings to light statements for contemporary figures in Western society, who spoke favorably of Prophet Muhammad, may Allah exalt his mention.
Author: AbdulRahman Bin Abdulkarim Al-Sheha
Translators: Abdur-Rahman Murad
Publisher: Islamic Propagation Office in Rabwah
Source: http://www.islamhouse.com/p/1385
This treatise was prepared by the Agency of Islamic Enlightenment in Hajj. Includes a discussion about those things which nullify a person's Islam as well as common errors made by the commonfolk.
Author: Muhammad ibn Saleh al-Othaimeen
Source: http://www.islamhouse.com/p/1377
The Muslim Creed - 'Aqeedatut-Tahaawiyyah.
Author: Abu Jafar at-Tahawi
Translators: Suhaib Hasan AbdulGhaffar
A nice book covering many aspects of wudoo, ghusl, tayammum, and wiping over socks and bandages.
Author: AbdulRahman Bin Abdulkarim Al-Sheha
Source: http://www.islamhouse.com/p/1381
Introduction to history of polytheism and monotheism: Allah (glory be to him) created all people as Muslims and monotheists but devils came to them and changed and distorted their religion. Allah said in a qudsi hadith, “I created all my slaves as haneefs (monotheists), but the devils came to them, made them deviate from their religion, forbade them that which I had permitted to them, and commanded them to join partners with me for which I has given no authority.” As soon as people commit a type of polytheism, Allah sends his prophets to call them to the suitable type of monotheism.
Author: Ameen Al-Ansaari
Publisher: A website Knowing Allah : http://knowingallah.com