Welcome to the forum!
Your best bet would be to call:
OMAHA NEBRASKA A.A.
4901 Dodge Street
Omaha NE 402-556-1880
And, to ask them those questions on the telephone. The people that answer the phones are AA Members that volunteer their time and efforts to answering those questions and to give you accurate, specific meeting times, locations and meeting format information, in order to be of help to other alcoholics.
Best wishes and keep coming back -- even after you call them. We want to know how you're doing and we'll try to answer any questions for you that they may not be able to answer adequately for you.
As far as I know, the Omaha Central Office does not have a website with the information -- just their telephone number.
re: "Is anonymity protected well?" No, it isn't protected or guaranteed. The anonymity -- is a spiritual principle -- and no one can force anyone to keep spiritual principles or Traditions. However, the person that breaks your anonymity -- if they do -- is guaranteed to suffer for breaking it.
What you might want to do if your anonymity is top priority for you is: Use an alias, just like an online "screen name" and not tell anyone your real identity. You don't have to mention that you are doing this. It would be better not to mention it. Just make up a nickname and use that until you feel comfortable -- if you ever do feel comfortable with it.
You asked: "how important is it to ones recovery, to physically be at these meetings?"
Answer: The meeting attendance is not going to keep you sober, nor will they alone -- produce recovery. However, my experience has shown me that most members do not stay sober -- if they aren't doing something to actively help other alcoholics.
You asked: "If one suffers from alcoholism, is researching and self help an option, or is it not strong enough without the group help."
Answer: My experience has been, much the same as mentioned in the book, Alcoholics Anonymous (the basic textbook for AA) -- Self-knowledge, knowledge about alcoholism and research and self-help, will not be enough to recover from alcoholism.
In regards to "group help": Many alcoholics got sober and stayed sober without group help. They simply read the book Alcoholics Anonymous, and began following the instructions in the book. Then, when they came to the instructions regarding "helping other alcoholics" -- they started searching for alcoholics to help. As they helped more and more alcoholics -- eventually, they started another AA group -- or, joined an existing one.
Most members do find it easier to find alcoholics that already have a desire for sobriety -- that show up to the meetings and the groups. It saves you a lot of trouble of going out and learning how to find them, and then helping them on your own after you do find them. And, most members find that staying sober -- is easier and more conducive -- by joining a local group and participating with the group.
I hope that helps.