A nice discussion of some important points needed by those callling to Islam
Source: http://www.islamhouse.com/p/1243
Ibn Taymiyyah said: "This (enjoining good and forbidding evil) is a duty that the entire Ummah is obliged to fulfil. It is what the Ulama know as an obligation of collective responsibility, if a group in society undertook to discharge it, the other members of this society are absolved from it. The entire Ummah is commissioned to undertake it, but if a group therein was responsible for discharging it, the rest of society is no longer obliged to undertake it."
Author: Sheikh-ul-Islam ibn Taymiyyah
Reveiwers: Muhammad AbdulRaoof
Translators: Salim Abdullah Marjan
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
This colorful book is for non-Muslims who would like to understand Islam, Muslims, and other facets of Islam.
Author: I. A. Ibrahim
Publisher: http://www.islam-guide.com - Islam Guide Website
Source: http://www.islamhouse.com/p/1221
A discussion of the obligation of keeping a beard and a clarification of some common misconceptions.
Author: Muhammad al-Jibaly
Publisher: Al-Kitaab & as-Sunnah Publishing
Source: http://www.islamhouse.com/p/1231
Sahih Muslim includes sayings, doings and approvals of the Prophet Muhammad (peace be upon him) narrated by his companions. It is considered the third most authentic book in Islam after the Quran and "Sahih al-Bukhari". It covers almost all aspects of life.
Author: Muslim ibn al-Hajjaj ibn Muslim al-Qushairi an-Naisabori
Translators: AbdulHamid Siddiqui
Publisher: http://www.islamspirit.com - Islam Spirit Website