There are a few things that you need to know when it comes to shopping for health insurance on the internet.  I will attempt to describe how the internet health insurance scene works.
There is HUGE competition on the internet for your business.  If you do a search for health insurance, you will find that around 90% of the internet sites claiming to get health insurance quotes for you are actually LEAD GENERATION sites.  These websites are written in such a way that you think that you are going to get quotes instantaneously.  Careful reading of the fine print will quickly tell you that these websites are simply selling your data to insurance agents that have agreed to purchase your information from these lead generation sites.
One of the quickest ways to determine if indeed the site is a lead generation site is to check the contact tab.  If you cannot find the name of an individual or the contact information is somewhat vague, this website will most likely be a lead generation website.
There are companies that are dedicated to creating websites that have very high page ranking so that they are always listed in the top 10 of all searches for health insurance, this is how they make their money, selling your information to agents that are trying to find people to talk to.
So what is the problem with entering your information into one of these websites?  If you are prepared for your phone to ring off the hook with companies trying to get your business, the quickest way to make that happen is to input your data into one of these lead generation websites.  My experience is that many of the phone calls that come from putting my information into these lead generation websites are mostly from captive agents that want to close a deal with you without giving you a chance to check other options, often called a one stop close.  There is a reason for this, generally there are better products available, but because they are captive and make their living from this one product, they have to sell their product at all costs.
If you are genuinely looking for someone to help you, look for a website that has someone that is prepared to publish their name on the website, a local phone number in the area where you live and also a toll free number.  Also look for a website that is able to provide you with actual real time quotes right there on their site.  Pick up the phone and talk to a live person, find someone that is prepared to find out exactly what it is that you want from your health insurance.  If you feel the slightest bit of sales pressure, ask yourself the question why, most likely the agent you are talking to is either captive, or makes the most commission from the product they are steering you towards.  Always take the time to make sure that you understand everything that you are being told.
Finally, independent agents that can give you quotes from multiple companies are generally the safest people to work with.  They have your best interests at heart and genuinely want to help you.
One agency that I have found to be very helpful is the Solutions Insurance Agency.  You never get a hard sell, and will always get the facts.
Happy shopping.