how much is a person reimbursed for being an executor of an estate

There is no "set" fee.  It is usually a small percentage of the value of the estate, depending on the value of the estate.  It could also be done hourly.  Many times, executors don't take a fee if they are a beneficiary under the will.  The fee does have to be "reasonable", and the amount can be challenged in the courts to determine its "reasonableness".