Your Mom had a will?
If so, then there is probably nothing you can do. A quick search of Ohio probate statutes does not show a provision for an "ommitted child" other than a "pretermitted child" -- if you were alive before your Mom made the will, and your Mom knew it, then you are not "pretermitted." You can peruse the Ohio codes yourself here:
http://onlinedocs.andersonpublishing.com/oh/lpExt.dll?f=templates&fn=main-h.htm&cp=PORC
Am I intitiled to property, if anything at all? If so, can the family sway the probates decision of what to do with the property, so that they benefit? My brother was listed as heir to all of moms assets.
Like I noted above, if you are left out of the will, most likely that's it. You can check with the probate court in the county in which she died in order to find out what is going on, but if you are not an heir, you don't really have any "rights" here.
In your brother's case, Ohio has an "anti-lapse" statute, which means that when your brother predeceased your Mom, your brother's heirs -- his children, most likely -- "step into" your brother's shoes, and would be entitled to his share.
Now -- if your brother died and he left no living children, or at least no children that survived your Mom, then things get a bit more complicated, and it would be time to see an attorney. If there is nobody alive to "step into" your brother's shoes, then the gift to him will lapse, and what happens to his inheritance -- whether it goes to intestate takers (which would likely include you) or into a residuary clause in the will (if it had one) -- will depend on the specifics of the will and Ohio law.
If you think something fishy is going on, then it might not hurt to speak with a probate attorney who can review all of the facts of your situation.