Can i execute LAN Extension with Linksys Wireless Router?

A Range Extender in the other building if it is in Line of Sight with no obstacles between the 2 buildings which can disrupt the Radio Signals. Under ideal conditions WiFi has a range of 500 metres though that is very marginal at that distance under most cases.

Here it all depends on what is between the 2 buildings which could interrupt the Radio Signals and how many systems you need to connect from the other end. Remember that the more computers on the Child side of the Range Extender the slower the Connection speed is going to be. Even with the Best WiFi you will be expecting something like 54 MBS in Data Transfer and they is the total that will be shared between the computers at the other end.

http://en.wikipedia .org/wiki/Wireless_range_extending_device

Just remember to remove the space from between the Domain Name and the .org

Col

Cisco makes some very nice WLAN bridges, and there are some cheaper alternatives from Linksys, Netgear, and others.

If you have clear line-of-sight between two buildings, as the Col mentioned above, 300 meters MAY be possible even without a special antenna. However, to ensure that the connection is fast and reliable all the time, even when it's raining, you would need a directional antenna on each bridge. With the proper directional antennas, it's possible to extend a WLAN bridge for literally miles (ranges of 4-6 km are very possible).

Personally I have setup this sort of device within large warehouses, between a main building and the 'guard shack', and even across a busy highway in Hawaii (sadly did not get to go there to test it).