If you have doubts about organised religion...forget them for the time being. Religion takes God a step further. First establish what you believe God to be.
Philosophers have come up with their own definitions of God through the ages. Here are a few:
Richard Swinburne:
God is disembodied, omnipotent (all powerful), omniscient (all knowing) morally perfect and completely free.
St Anselm:
God is the greatest possible conceivable thing.
Descartes:
God has all perfections.
Alvin Plantinga:
God has maximal greatness or maximal excellence in all worlds.
Norman Malcolm:
God is not contradictory.
Classical Definition:
God is disembodied, omnipotent (all powerful), omniscient (all knowing), a free agent, the creator and sustainer of the universe, wholly good, and worthy of worship.
These are philosophical definitions of God, which came from philosophy which came long before organised religion. For example, Christianity, Judaism and Islam are based on the teachings of Aristotle. As you can see, all these definitions say more or less the same thing. The most important thing about God, is that you believe he not only exists, but is worthy of worship.
Unfortunately, as you pointed out, organised religion is full of contradictions, in the Bible for example. There is a very good reason why this has occured: the Bible was written by men, who are not perfect, not by God. God did not write the Bible, so my suggestion is that if you are looking for the truth about God...you don't let yourself get to bogged down with all the scriptural details.
In organised religion this is indeed what happens. In several sects of Christianity, every detail of the Bible is studied and taken into account. A lot of these details are not important. People should instead concentrate on the overall message of the Bible, which is that, God came down to Earth, and sacrificed himself as Jesus so that humans would be cleansed of sin and could reach salvation.
(Now similarly, philosophers have proved the existence of God in different ways. Some I accept...others I don't. I would be only too happy to explain them to you if you want me to, but I'll leave it for now because it will be extremely lengthy.)