You may check the Linux Laptop, PDA and Mobile Phone Vendor Survey at TuxMobil for a reseller in your country. Some of them even sell laptops without Microsoft operating systems.
Often it is difficult to get laptops without a pre-installed Microsoft operating system. In case you do not want to use it you may read some tips and tricks to get rid of the Microsoft tax. If you want to buy a recent machine check the Linux installation reports for recently available laptops and notebooks.