My father verbally "disowned" me after what he said was my calling him and "his family" names on a phone call. We had the phone call but there was no name calling and he was (as usual) drunk at the time. 2 hours later I got an email from my sister saying to never contact any of them again. He died in May of 2009 and I heard from my half brother that my sister's daughter got everything. Is there any way that I can fight this now? I am not in touch with anyone but my half brother. Thank you.

Depends on what actually happened. Since it skipped over siblings (direct children) there has to be a paper trail to prove it. You need to find out what happened.

If your father left a valid Will his estate will be distributed as he requested - very possibly with nothing to you.