Demonic Tutor and Unholy Strength are the only two I know of.
Unholy strength only features the pentagram in the Alpha, Beta, Unlimited and Revised printings. The 4th Edition printing removed it from the background, and subsequent printings featured different art.
41
A lot
Either 8 or 15 cards.
Single cards that represent a creature (token) there are currently 199 that I am aware of.
Retail stores and online, many stores will ship to India
Magic the Gathering has many formats, each with it's own list of legal cards. To see a complete list see here: http://www.wizards.com/Magic/Magazine/Article.aspx?x=judge/resources/banned
There are over 60 Magic The Gathering FAQ on WikiAnswers.
Booster boxes of magic the gathering can be picked up at most trading card stores. Or online at many gaming websites. Some that I have personally used are www.trollandtoad.com and www.starcitygames.com. Both sites offer booster boxes, and singles so you can order single cards that you may be looking for. I hope that helps.
Your local card store will have basic land cards that you can purchase or trade, they may even give you some depending on how many you need. Many, many online stores can sell you basic land cards. Other players may have spare land cards that they can part with.
90 and still more
not enough
At the beginning of the game each player draws 7 cards