To cause someone to call you:
In African-American hoodoo, there is a belief that the use of black candle tobacco (twist tobacco, not flaked) is efficactious in this regard. Folks may soak it in whiskey and then sprinkle a bit of the liquid and the tobacco in their mail box to draw a letter, on their phone to draw a call, or, i guess, on their computer (carefully!) to draw email.
To maintain contact at a distance:
Sleeping with a packet of calendula flowers, althaea leaves, and a few star anise seeds under your pillow is said to draw communications from a distant person through the medium of dreams. This means you will dream of them, not that they will necessarily dream of you. It is recommended as a good way to ascertain the state of health and well-being of someone you miss and may be unable to contact directly.
White Magic Spells Chants
Source: i-love-witchcraft.blogspot.com