You have to wait for the probate to be opened. If you are a beneficary under the will, you should get notice. If you don't get notice, look on LINX (google Pierce County LINX) for the probate and see what it says. Once you get notice your time to respond is fairly short - like thirty days.
Contesting wills is generally expensive and nearly always futile. Be sure that you have a valid basis and get good advice. Hope this helps. Elizabeth Powell
You can bring a will contest within four months following the acceptance of the will in probate.
RCW 11.24.010: http://apps.leg.wa.gov/rcw/default.aspx?cite=11.24
I concur with Ms. Powell's comment that it is difficult to contest a will. The usual grounds are incapacity and/or undue influence. Often these cases can be resolved in mediation. If you want to contest a will you should probably have solid medical evidence ahead of time as to the basis for legal incapacity.
Sometimes the best defense is a good offense. You can, for example, open a probate with a competing will, or based upon intestacy (absence of a will). This puts the burden on the other side to bring the will contest.