It depends on the type of case, DA policies, judicial policies, specific DA, and specific Judge, but the odds are pretty good that showing up and dealing with the case be it plea, trial, jail, or probation is the only real way to get it resolved. To get a concrete answer, hire a lawyer from Florida to represent you and see what he or she can do for you. Don't expect this to just go away.
You need to hire an attorney in Fl. You need somebody who can look into the case and who can try to set it up so that you can come down to court without being arrested on the warrant. The sooner you take care of this the better as it won't go away.
You can contact Ms Joffe at 303-757-6572, Legal disclaimer: We at the Joffe Law FIrm wish to help you. While the above answer is intended to provide general information only, does constitute legal advice, and does not create an attorney client relationship. We strongly suggest that you seek legal counsel.
My colleagues are correct. Search for a criminal defense attorney in that area of FL on the FL Avvo site and hire them to see if they can take care of this without the necessity of you appearing. The attorney will know the practices of the judge and the DA. As a former judge, I am surprised that the clerk would encourage you to write an ex parte letter to the judge. That normally is not allowed.
The information provided in this answer does not create an attorney-client relationship. If you are interested in his legal services, feel free to call Chris at (303) 409-7635 at his law office in the Denver Tech Center. All initial consultations are free of charge.