first of all checkout this guide
http://www.pakgamers.com/forums/f67/team-pakgamers-buying-guide-cpu-85616/
don't worry normal oc'ing is safe for your pc
you can purchase motherboard from astrontech lahore (astrontech.com.pk)
other stuff from iamextreme.net & galaxy.pk
not really but you know this is electronics & nobody can give you warranty so its better to take care of stuff and always purcahse products in warranty + if possible use UPS
if you want to play games on full hd you need a better budget for graphics card like i will try to fit a good gpu in your setup. with this gpu you can easily play upto 720p and even on higher resolution.
as both are available in almost same price its better to get LED because there are some advantages of LED like less power consumption & its new technology.
no need to purchase a sound card if you don't have a powerful sound system and specially in this budget its useless to purcahse a sound card
now i suggest you to go for this setup :
processor---core i5-2300------------------16800----galaxy.pk
ram----------2gb KVR 1333mhz------------2000-----galaxy.pk
mobo--------H67MA-E45(B3)--------------9900-----astron.com.pk
casing-------Antec 600---------------------5800-----iamextreme.net
psu----------ANTEC EA500----------------3800-----galaxy.pk
gpu----------Sparkle GTX460--------------16500---iamextreme.net
hard---------seagate 500gb 7200.12----3800----galaxy.pk
optical------liteon 24x dvd RW------------2200----galaxy.pk
-------------------------------------------------------------------------
total-----------------------------------------60800----------------
this pc is overclockalbe but if you want extreme overclocking you have to expand your budget for this then you can purchase core i5-2500k & msi p67-gd65 both are avaialbe in about 20+20k= 40k so you have to expand your budget to about 80k
with gtx460 you will be able play games games on 1080p & but you have to get 2 gb more ram but right now this setup is enough for you.