At any Lego Store
You can buy legos from the Lego store, target, walmart, toys r us and more!
At your nearest Lego store or Walmart.
Sadly Lego costumes do not exist, however you can buy weapons etc. from your nearest Lego store.
You can buy them at usually any Lego store or online
You can buy a Lego blind bag from a toy store such as Toys R Us.
You can, but most people buy it online.
As far as I know, only the online Lego store at shop.lego.com.
national book store
You can buy LEGO Master Builder Academy Kit 1 (Space Designer) on the LEGO Shop website (shop.LEGO.com) or at a LEGO Brand Store.
At a local toystore? Or if you have a Lego store then definitely there. Legos are basically everywhere.
This set is a Toys R Us exclusive. Which means you can get it there OR buy it directly from a Lego retail store or shop.lego.com