You want to cast a circle but don't have an athame or wand, use your finger. After all, neither of these tools has any power of their own. They are simply conduits for your own energy.
Calling the quarters...you don't have any thing to represent them? No problem, visualize what you feel represents each element in its quarter. For example, a bonfire in the south.
Candles must be charged with energy for the purpose of the spell. You can simply send the energy out yourself without using a candle. The same goes for incense.
You don't have anything to represent the Lord and Lady? Do you honestly think that they will forsake your request because you don't have candles or figurines to represent them? Pray, they will hear.
As for an altar, anything can serve as one, you don't need a permanent altar. In fact you don't really need one at all. The altar holds your tools and you can do an entire ritual or spell without any tools.
The tools are simply a way to put you in the frame of mind to do the work.
Suggested ebooks:Elizabeth Reis - Confess Or Deny What A Witch To Do
Michael Ford - The Book Of The Witch Moon
Anonymous - So My Kid Is A Witch