1. Iman increases and decreases. In each persons life, he will experience up and downs in the road, as will his iman. Iman is at its peak when things seem like they couldn't be any better or it can be at the lowest point when the road is bumpy and we feel weak in faith. Iman decreases from sin, whether they are big or small, they will slowly eat us away. Sin leaves us feeling depressed, empty, and makes us lose hope also, as at tiems we might think that we dont deserved to be forgiven. The way to get out of this sin is asking sincere forgiveness from Allah, and once we recognize that, and start doing good deeds, inshallah our iman will increase. Allah says in the Qur`an, "So verily, with the hardship, there is relief. Verily, with the hardship, there is relief." (94:5-6). We must realize that whatever condition we are in is only temporary, and Inshallah Allah will make it better if we ask him, and soon good times will come. This is a good du`a that the Prophet used to make to ask for forgiveness, "O Allah, forgive me my faults, my ignorance, my immoderation in my concerns. And Thou art better aware of my affairs than myself. O Allah, grant me forgiveness of the faults which I committed, seriously or otherwise and which I committed inadvertently and deliberately. All these failings are in me. O Allah, grant me forgiveness from the fault which I did in haste or deferred, which I committed in privacy or in public and Thou art better aware of them than myself. Thou art the First and the Last and over all things Thou art Omnipotent." (Muslim)
2. There are 6 pillars of iman, beleif in Allah, beleif in Angels, beleif in all books sent by Allah, beleif in all His Messengers, beleif in the Day of judgement, and the Divine decree, both good and bad.
3. Allah has told us the names of some of them, such as: Jibreel, Meekaal, Israafeel and Maalik (the Guardian of the Hell-fire). The Prophet (SAWS) informed us of Munkar and Nakir (two angels who question people in the grave).
Website i used for help:
http://www.islamweb.net/ver2/mainpage/indexe.php
v. good website, has a lot of stuff
May Allah reward u for this thread.