The kalam cosmological argument has been developed in the last few decades by William Lane Craig (PhD, University of Birmingham). The argument goes as follows:
1. Whatever begins to exist has a cause of its existence.
2. The universe began to exist.
3. Therefore the universe has a cause.
(Craig also develops certain reasons why the best explanation for the cause of the universe is something akin to the Christian God.)
One frequent objection to this argument is that “If everything has a cause, then what caused God?” But this objection fails to understand the argument correctly. The argument does not say that “everything has a cause” but rather that “everything that begins to exist, has a cause.” Since God did not begin to exist, there is no (external) cause of His existence.
For a more complete explanation and defense of the kalam argument see: http://www.leaderu.com/truth/3truth11.html