One game that always had a LAN play side is Americas Army. Version 2.8 , the last one before going to Steam let you do that as well and it is a free game. I haven't been able to part with the $60 required for Arma yet.
You should... there is a good deal of community content for Arma, if you are looking for something more than the cod/bf style shooters.
If you have a group to play with, alot of the player made missions are absolutely a blast to play. And alot of the community spins them into a series. One of my all time favs was a player made series where you were a rag tag militia/resistance fighter and had to over throw the local military regime through a series of missions... it was spectacularly put together, the enemy had much better weapons, equipment and vehicles. Where as your load outs were always randomly thrown together so you would have a couple pick up trucks or a car or so. Then some people would have on like shorts and a tee shirt. Some may have spawned with an assault rifle others may have only a pistol. Some people may only have 1 mag for their rifle... none the less it was an awesome story line and worth the 60 bucks on its own haha... I also like a majority of the convo missions where you have to lead/ guard a convoy or ambush one. There is also a running mercenary mod where completing missions gives you more money to buy better gear and equipment and you have to purchase absolutely every you need from weaps down to bullets and fuel.
And thats not even to mention the more common multiplayer player play mods, such as king of the hill, arma life, wasteland, annex and invade, invasion, and prolly one of the most important; breaking point.
Deff worth it.... but you really have to like the complexity it offers over the "typical" shooters other wise you will grow frustrated quickly and will prolly never touch it again.