Undoubtedly, the heart leans towards those who are kind and gentle. It was said a long time ago: "Make your face happy and your words gentle, and you will be more beloved to the people than those who give them a gift". The one calling to the religion of Islam and dealing with other people has the utmost need to gather the people around him, and cause their hearts to lean towards him so that they will listen to him. Adorning himself with kindness and gentleness helps to achieve that goal with the grace of Allah.
By The Imam, the Hafidh Abu Hafs 'Umar bin 'Ali al-Bazzar. Translated By Abu Sabaayaa. “If I had to swear standing between the corner of the Ka'bah and the spot of Ibrahim, I would swear that I have not laid my two eyes on anyone like him, nor has he seen anyone as knowledgeable as himself.” - al-Hafidh adh-Dhahabi
Author: Omer Bin Ali Al-Bazzar
Saheeh International, based out of Saudi Arabia, Translated the meaning of the Quran in English, which is most appropriate for non-Muslims, it is easy and clarity of words and meanings.
Publisher: http://www.islambasics.com - Islam Basics Website - Sahih International
A brief but nice booklet discussing Zakaah, those items and amounts upon which it is due, and where it is to be spent. Includes a few important fataawa related to Zakaah
Author: Abdul Aziz bin Abdullah bin Baz
Source: http://www.islamhouse.com/p/1269
Fiqh us-Sunnah
Author: Sayid Sabiq
Brief lessons in fiqh, da'wah (calling to Islam), Creed and hadeeth and its terminologies taught in the Educational Department of Islamhouse. They help Muslims to be aware of what he indeed needs regarding the Islamic sciences. They also give him a glimpse of qualities of the caller to Islam.
Publisher: Islamic Propagation Office in Rabwah