Christmas is this Friday, December 25th! There is still some time left to get your order delivered before Christmas. For LEGO Shop at Home (USA | Canada | UK), order by noon EST, December 22nd, 2015 using the express shipping option. For Amazon.com, the last day for two-day shipping would be on Tuesday, December 22nd, 2015. For Amazon.co.uk, the dates vary a little so make sure to check the UK Holiday cutoffs.
In addition, you can always visit one of your local Brick & Mortar retailers (I.e Wal-Mart, Target, Toys R Us) for LEGO toys as well!
Amazon USA order cutoff dates