Make an Inventory of Information Received:
Make a list of every item you receive, broken into a work category and a personal category. Note two details for each item on the list: the subject or type of data and the method of transmission. Use this inventory to think about what you receive, how it reaches you, and whether or not each one is working as well as it could for you. If it is not, think about other ways you could receive the same information that would work better for you, and make that change.
Make an Inventory of Your Devices:
Not only do we need to consider the data, and the mechanism for their input, but the devices we use to access that data. I have a choice about accessing my work email; I can use any of three different computers or my smart phone. I have a choice about what device I use to talk to my parents; do I use my home phone or my smart phone? Consider all of the devices you use, and add a third detail for each of the items listed in your inventory: what device do you use, and whether or not you should use a different one.
There are many books about information overload and dealing with information generally. Here are some of my recommendations: Information Anxiety and Information Anxiety 2 by Richard Saul Wurman, Take Back Your Life!: Using Microsoft Outlook to Get Organised and Stay Organised by Sally McGhee, Techno Stress: The Human Cost of the Computer Revolution by Craig Brod, and TechnoStress: Coping with Technology @ Work @ Home @ Play.
LOL - catalogue everything and read lots of books. I guess librarians have a different sort of information overload :-)