Re: black magic
Somebody I know had been effected by it. Its a very hard & dangerous test.. whatever happens, don't lose your faith (i.e. by submitting to those who performed it on you). If you do, it will be an act of shirk.
Some Hadeeth & Quranic Verses that are helpful in such situations:
Narrated Abdullah ibn Abbas:
The Prophet (peace_be_upon_him) said: If anyone continually asks pardon, Allah will appoint for him a way out of every distress, and a relief from every anxiety, and will provide for him from where he did not reckon.
*Dawud :: Book 8 : Hadith 1513 *]
'A'isha reported: I heard Allah's Messenger (may peace be upon him) as saying: There is nothing (in the form of trouble) that comes to a believer even if it is the pricking of a thorn that there is decreed for him by Allah good or his sins are obliterated.
*Muslim :: Book 32 : Hadith 6241 *]
And surely We shall try you with something of fear and hunger, and loss of wealth and lives and crops; but give glad tidings to the patient, Who says, when afflicted with calamity: “To Allah We belong, and to Him is our return”: They are those on whom (descend) Blessings from Allah, and Mercy, and they are the ones that receive guidance.
Al-Baqarah 2:155-157 ]