One of the first things any good financial adviser will ask is if you have a will.
Thinking about death and wills and life insurance is never fun, so many people put it off as long as possible. If you can force yourself to think about it for a few minutes, it helps to have some structure. People who don't want to hire a financial adviser to provide that structure can get it from websites and workbooks.
I recently looked at a website called Everplans that offers a number of services for free, but charges for additional services like more storage and more "deputies" to access your plan. It provides a good place to store your key information online, like the location of your legal documents or even copies of your legal documents if you wish.
The user interface is very friendly. Walking through the process will let you identify what planning steps you have completed and what more you need to do.
There are many alternatives to Everplans, like AfterSteps.com and Principled Heart. A few are mentioned in this New York Times article.
These services are meant to help you organize your affairs and not to create wills or other legal documents. There are websites that do, but this is something I have always felt too important to trust to anyone other than a qualified attorney.
If you prefer to go old school, check out The What if. . . Workbook by Gwen Morgan.
Sometimes we just don't know what it is that we need to know and services and products like these can help.