You may not find many of those even for sale, especially .com; your best option may be to just decide on ones you want to pursue and then contact the owners directly.
I saw here available any LL domains but price is $250 http://www.nic.lk/facts.html *** I have friend there if you want help let me know
Constantly check on aftermarket auction sites. Though you may see some LL.com names that appear to be unregistered or expired, they are actually not available to the general public for registration. Also, you could hire a broker or someone to hunt a name down for you. What is your budget? .
As far as I know you can not register a 2 character domain name. The minimum is 3 character. You will need to search auctions/forums etc.