Do i have to buy insurance this month at the new health insurance exchanges that opened yesterday, or can i buy it months later, or even in 2014?

Take your time: As i understand it, you will need proof of your insurance when you file your tax return next year. Take your time and be aware of all the coverage, exclusions and out of pocket expenses of exchange based policies and compare them to those you can get from your local insurance market. Be sure you are ready to budget for the costs of each based not just on stated premium but all costs involved.

By 12/15/13: As i understand it, if you want insurance to begin on 1/1/14, you need to select a plan by 12/15/13 or you might be delayed. So starting now you still have time to research the best plan for you ; your family. I like dr. Ferguson's suggestions as you do this. Good luck to you. I'm so glad more people will have access to insurance, and hope the current gridlock over it is resolved soon.

Few months to enroll: There will be an "open enrollment" period from oct 2013 through march 2014 at covered california, the marketplace for california. If a person waits until after march to enroll, she might not be able to get insurance for 2014 through the marketplace, unless she has some special circumstances (such as losing her job, birth of a new baby, or death of a spouse).