How does one obtain the balance of a retainer from their lawyer? My lawyer avoids my phone calls, emails and text messages.

NRPC 1.15(d) governs safekeeping of client property, including fee advances and retainers, and return of the same.   "Except as stated in this Rule or otherwise permitted by law or by agreement with the client, a lawyer shall promptly deliver to the client or third person any funds or other property that the client or third person is entitled to receive and, upon request by the client or third person, shall promptly render a full accounting regarding such property."  Your attorney has a duty to keep the State Bar of Nevada apprized of the most recent address.  Check with SBN in order to get your attorney's most recent information.  If you cannot get an accounting of your fees, you may wish to seek mediation or arbitration through the State Bar of Nevada Fee Dispute Program.