The Official Medicare Website

• The first and most important stop for anyone comparing Medicare D plans online is Medicare.gov, the official Medicare website. The "Formulary Finder" allows you to enter in your location and prescription information, giving you a list of plans that cover the drugs you need. The list also includes each plan's contact information and ratings for each company based on their customer service and complaint history. This list can help you narrow down your plan choices significantly.
  
  

Plan Websites

• Once you have a few plans in mind, the website for each plan can provide more details, including the formulary (list of drugs), application information and pharmacy list. Each site will also have sales content; it's important to look past that and focus on the facts of each plan. Confirm the information Medicare provided, as well.
  
  

MedlinePlus

• Another source for more general information to help compare prescription plans is the Medicare Prescription Drug page on MedlinePlus, a website developed by the U.S. National Library of Medicine. There's information on recent plan changes, and you can sign up to be notified for plan information via email.