My local gaming magazine gave us these for free:
EMNW4-CKF8W-TYRHX v 88YER-Z2ZK3-A09L9
49AF0-2R0L7-C24RV v WBZFH-ZXRMZ-VDMF6
PCQ0T-ZTK65-XD8I9 v E3J3G-RJYE0-NCF0E
HX9X8-JWPK3-TMTJR v WI2M8-BI655-TDLTT
VC3EB-GHLIG-09Z4V v 73F72-8JMRY-6BHG0
7EZWR-R5Q4A-94P6K v PV263-RM96R-Y9WRX
V9H8P-QJM5H-KIEZZ v C6M9M-FY4EM-XCMMZ
NPL3I-HKHET-BFWCL v CC85R-7AIYE-VCQVP
677HF-GJLER-PRWT4 v HGMER-KPC4Y-P320K
GZMB7-T72CR-G87H7 v K7TT9-LLKG7-CAMFK
More here : Arma 3 Alpha Lite Giveaway (II)