I've heard a lot of mixed feeling about buying laminate online. Frist, you always want to make sure you can see your flooring in person, so if you do buy online, be sure to order a sample first and put it through a durability test (see what it takes to scratch, stain, etc). The other thing to worry about is acclimation. If you order your laminate online and it comes from a dry climate and is delivered in a humid climate, or vice versa, you could have acclimation problems.
In my opinion, you should support your local retailers. That way, you will have an actual person to talk to if you have questions or if something goes wrong. I bet that lumberliquidators would just tell you to contact the manufacturer whereas your local retailer will do what they can to help you in order to maintain your trust. Also, be sure to check out the laminte buyers guide here www.findanyfloor.com/BuyingGuides/...
to make sure you are buying quality laminate.
Good luck with your flooring purchase!