I've not had chance to play Arma yet - but Humble Bundle are currently doing an ARMA bundle - for £15 ish, you can grab yourselves a copy of lots of ARMA, including loads of the add ons (arma 2: British Armed Forces, private military company and Czech Republic).
Here's a link :
https://www.humblebundle.com/arma-bundle
EDIT: When I said £15... it's actually in $$$... so that turns out to be £12...
Hi Unhinged, welcome to dMw and the forum. If you've bought Arma 3 i hope to see you on our server soon.
Sulky has already posted about the Humble Bundle (http://www.deadmen.co.uk/forum/showthread.php?43299-Arms-is-on-humble-bundle&p=421956&viewfull=1#post421956). Unfortunately, as Puff says it doesn't include most of the DLC for Arma 3. I suspect we'll get some deals later this year when they start bringing out the new DLC for this year, including Jets and Tanks (https://arma3.com/news/arma-3-roadmap-2016-17#.WMexx_LuiZY).