Looking for is not an easy task, as the information provided free might not be that accurate. You might look for the SSDI (Social Security Death Index) but you should know that only reported deaths are found there. There are many relatives to a deceased person that will not find useful to declare death. This is why, if you need more accurate dates, you might need to look for a specialized service in this field. This kind of service is never free, as researches will cost money. Do not worry, as the money spent by you will go to researches also. You will also be sure that they will come with more and accurate statistics needed for your researches.
Find a service that provides you a search engine. You should be able to use filters like names, cities, date of birth and death, and the last known address. A detailed database is useless if you need to scroll between millions and millions of records. Be sure the government authorizes the site also, as there are many sites using fake dates to charge you.
You should also know some common tips about searching Use maiden names when searching for females, as you could also build a Genealogy tree with this. Sure, you can find that person by the marital name, but this will not help you in finding her parents and ancestors. Another tip is to search using just a few facts. A possible births period and the maiden name can be enough for the start. If the result is very large, you might have to complete your search with additional dates like place of death and spouse name. You should also have a tool at your disposal to look for misspelled names, as this is a common problem especially in the early years of statistics.
Finding dates about this topic is not only for statistical and researching. You can always search for personal information purposes. You might find important dates as common death causes in your area. This will be helpful as you could be protected this way. Let us say that bee stings and snake poisonings are common in your area. You should be aware of this aspect in order to protect yourself, and can be a useful tool for this.