A temporary sponsor is a good idea if it makes you feel more comfortable with this whole thing. All in all ~ every sponsor is 'temporary' and should only lead you through the steps.
The big book is AA (fellowships name was taken from the title of it's Book - you can read that in the book itself). Some call it the BS sifter, and I think that is an accurate description and good to know in any case. You will get a lot of opinion on what AA is and what it isn't, I always go back to the book to see if something I hear is really "AA".
You are absolutely right to be skeptical about the "God" idea, there is a time and a place for everything...step 1 is not about God or Spiritual experience or anything of the sort. I can tell you up and down that AA is not religion, or a cult ~ but it is best to find out for yourself. Just remember when the time comes for consideration on these lines that god only has to do with "your understanding". My conception and anothers may be world's apart ~ what it really comes down to is surrendering to the fact that I have alcoholism and can't fix it...and tapping a power that is so simple it cannot be put into proper words ~ this power can relieve one's alcoholism. No one in AA is going to tell you what god is or isn't, no one (hopefully - and when this thing is being done right), will even try to convince you what to believe. The whole program is based on facts...it took me a long time to understand that.
Step 1 - you state that the urge to drink more once you have had a little occurs. This is not 'normal'...most people who drink alcohol don't experience this craving. (Craving, by AA definition, only occurs once alcohol is introduced to body of the alcoholic - the alcohol craves more alcohol and there is no way to "think" oneself out of it...
That is 1/2 of Step 1. The other being: "I cannot stay away from that first drink"...off goes the vicious circle of active alcoholism...when I drink I want more, and when I am sober, no matter what ~ I will drink at some point. Attempts at keeping myself sober have failed, over and again.
Unmanageable? This can be a bit of an involved topic, for someone in your shoes I would ask; "Is drinking causing problems in your life?" If it wasn't ~ there really wouldn't be a desire to quit (right?).
All the best ~ feel free to PM me (if PM's are working)..or question anything about this process. I don't see any reason you cannot recover from alcoholism, if you are alcoholic.
~a