It is best that you try to work this out with the attorney. Perhaps you should go try to meet with him in person. Maybe there is a reason why he is holding off on filing your case.
If you can't work it out, you should contact the local bar association and let them know what is going on. I suspect that after hearing from them he will be much more inclined to work on your case and return your calls. Otherwise, they may be able to force him to give you your money back so that you can hire someone else. Good luck.
Disclaimer: Please note that this answer does not constitute legal advice, and should not be relied on, since each state has different laws, each situation is fact specific, and it is impossible to evaluate a legal problem without a comprehensive consultation and review of all the facts and documents at issue. This answer does not create an attorney-client relationship.
There may be a reason your attorney has not filed, for instance, some firms only file on certain days or dates in a month so they are able to manage their calendar and avoid conflicts. From the date of filing in Bankruptcy Court, numerous deadlines and hearing dates are calculated, by only filing on certain dates in a month you are able to ensure that you are not calendared to be in more than one Court.
I do not know if this applies to your circumstance, so it is best if you make an appointment to speak with your attorney and find out why your case has not been filed. If your phone calls have not been returned, try writing a letter or email and see if you are able to make contact. If all else fails, contact the Nevada State Bar.