I don't know of any offhand, but the answer depends on a number of criteria:
1. Did the departed have a will, living trust or other valid document that addresses the disbursement of their belongings?
2. If not, is there more than one possible heir to the estate?
3. Does the estate have more debt than equity/belongings?
Unless the departed have set up something such as a living trust in advance, or prepared a will with the assistance of an attorney, the estate is likely going to have to go through probate in most states. In this case, a judge will ultimately decide how the estate is disbursed, and a trustee (lawyer) will be assigned to the case who temporarily manages (or mis-manages) the estate and is paid a certain percentage of the estate's value.
If there is no will, or a will is contested, the case could be in court for many years. If there is a significant amount of money at stake, most parties would be wise to hire their own attorney. Unfortunately, the trustee assigned to the case is often someone who has little interest in maximizing its value, so the estate may ultimately be worth much less than it was initially worth, especially if there are a number of ongoing expenses.
Unless a specific document written prior to their death has named you as the trustee, you can't really "make yourself" the trustee, legally. If the estate is very small, and you are the only possible heir, you might be able to get away with running the estate until its assets are "gone". However, you would not likely have access to things such as the deceased bank accounts, be able to transfer property, sell registered autos, etc. If anything like this is involved, you are best off seeking an attorney who will advise you on what to do. The case will almost certainly end-up in probate, but an attorney can help you maximize the value of the estate prior to handing it over to a judge and making sure that you get a fair shake in court.
Hope this helps to answer some of your questions.