Contact the agency directly and ask!
READ THIS BEFORE CALLING OR EMAILING ME: I am licensed to practice before the state and federal courts in Virginia. We have not established an attorney-client relationship unless we have a signed representation agreement and you have paid me. I am providing educational instruction only--not legal advice. You should speak with an attorney to whom you have provided all the facts, before you take steps that may impact your legal rights. I am not obligated to answer subsequent emails or phone calls unless you have hired me. I wish you the best of luck with your situation.
A subpoena has to do with getting you to appear at a legal proceeding - usually civil but it could be criminal. Are you aware of any proceedings that you might be called as a witness for? There is not really one central agency that serves a subpoena although many people use the local county Sheriff's department which has a division that serves legal documents, but there are many private outfits that also serve legal documents. it would really help if you could remember something about the document, was it civil or criminal? A warrant for your arrest is normally reserved for when you don't show up to a proceeding that involves you and being charged criminally. In a civil matter the Judge can be asked to send a Sherriff to find you and bring you to court if you don't show up when you were supposed to. It's really up to the Judge. If you are worried about a warrant you or anyone can call the police and inquire for you if there is a warrant out for your arrest. Most people would have an attorney call for them. Do you even remember what day the subpoena was for, like what day you were supposed to appear in court? If you know the court date you can go to the court and ask them what proceedings are scheduled for that date. But not all proceedings are held at the court so that may or may not solve your problem. http://www.portlandlegalservices.com
The comments by this author to questions posted on Avvo are designed to foster a general understanding of what might be the law governing the area of the legal problem stated and suggest what might be the approach to finding a legal solution. Under no circumstances is this author acting as the attorney for the party who posted the question or as the attorney for subsequent readers to the question or response and no attorney client relationship is being formed. This attorney's comments are not intended to be a substitute for getting legal advice from a licensed attorney. A reader of this author's comments should never act on the information provided in these comments as though these comments were legal advice and should always seek legal advice in a personal consultation with an attorney in their jurisdiction before taking action. The information provided here is not intended to cover every situation with similar facts. Please remember that the law varies between states and other countries and is always changing through actions of the courts and the Legislature.