After big effort recently i got installed ArchLinux on my Desktop PC. Now its up and running nicely with the KDE desktop environment.

I will describe here few stuff and problems that I faced during the Arch Setup on my real hardware, but i prefer who are interested to try it out on a Virtual machine first! 

This guide helped me alot, its a funny tutorial but all up to the points!

Video Tutorial

Troubleshooting 

few Notes encounter when I was installing Arch on real hardware/OracleVirtualBox

Internet not working after Installing the base system (after you restart)
Thats the effects of 
'systemctl enable dhcpcd@eth0.service' command

Regardless, the correct command now is:
systemctl enable dhcpcd.service

 http://www.youtube.com/watch?v=TBrbS5f8rnM

Configuring pacman

The SigLevel option in /etc/pacman.conf determines how much trust is required to install a package.

If you get some problem like:
error:

open pacman conf and edit

SigLevel = PackageRequired >> SigLevel = Never

Guide to install Sinhala Unicode Font

Download and Install lklug.ttf Sinhala Unicode font file

sudo pacman -S wget
sudo wget -P /usr/share/fonts http://sinhala.sourceforge.net/files/lklug.ttf

Then Run the following command

fc-cache -fv

And proceed to the below steps..

Enabling Sinhala Locale

Edit /etc/locale.gen. Uncomment following line

si_LK UTF-8

Run following program

locale-gen

Immediately you'll be able to read Sinhala Unicode in your programs (If not You may need to restart the relavent programs. eg: Firefox)