I have suggested in other posts that God isn't something because He is everything. I know this is difficult. It sounds weird. "Pat," I can hear you saying, "He would have to be something if He were everything." Perhaps. But the following excerpt from the book, "God (A Guide for the Perplexed)" by Keith Ward, may aid us in the paradox; albeit with his discourse on time. (page 134)
"Time, despite Aristotle, did have a beginning (most modern physicists would agree with this). You can always ask, 'What existed before the first moment of time?'--but the question does not really make sense. It is like asking, 'What positive integer exists before the number 1?' The answer is that it is the first positive integer. So, if time is a relation between events, and there is an event that is not preceded by any other event, that is the beginning of time. No problem."
"God, however, is the creator of time. So God does not exist before it. God must exist completely outside and beyond it, not in a temporal way at all. God is absolutely timeless. In God there is no before and after, and God does not exist at any time. It follows that God does not now exist."
"The point is that God does exist. But there is no time at which God exists. The whole of time, from beginning to end, is created by God. Because of that, it is just as true to say that God creates at the end of time as it is to say that God creates at the beginning. If we imagine the whole of time as a line from A to Z, then the whole line is made by God in one and the same act." (all emphasis mine)
I think this argument is easier because we can picture a distinction between God and time. The position that there is 'no time at which God exists,' is an understandable concept (time being a byproduct of God's creation). It may be more difficult to embrace the idea of God not being something. It is the limitations of something, the inherent specificity of the word, which makes it inapplicable. Just as God is nothing (no thing) neither is He something (some thing). He is everything. (every thing)
Of course there may be those who claim this is all a matter of semantics. They would not be wrong. When it comes to God we can't be sure...even if we insist we have had a divine revelation. Many have had revelations (Abraham--Moses--Jesus--Mohammad--Joseph Smith, etc). Are we to believe that God has altered His message? Revised it? Updated it? Or can we allow for personal visions that are consistent with a universal longing for that inexplicable something that is everything we ever dreamed of? Time will tell.