hi guys please where can i buy this parts in Qatar in order to build my own gaming desktop please give me the best place some ones tell me tornado store or some thing like that but expensive right !? and buying through the internet is risky

Case(i want only a good case not Necessarily those cases) : CM Storm Enforcer
Raidmax AEOLUS ATX Mid Tower Case ATX-818WB

CPU:Intel Core i5-2500K
or
Intel Core i5-3570K
or
Intel Core i7-2600K

Motherbord:GIGABYTE GA-Z77-HD3
or
GIGABYTE GA-Z77X-UP4 TH
or
GIGABYTE GA-Z77X-UD5H

GPU:NVIDIA GeForce GTX 670
or
Gigabyte's GTX 660 Ti
or
NVIDIA GeForce GTX 680

and many other Stuff

and thank you guys i hope that you give me the right answers :)