For more information and to purchase online:

The Complete First Season
http://www.amazon.com/exec/obidos/ASIN/B003R4ZMS6/ref=nosim/happydaysonline3-20

The Complete Second Season
http://www.amazon.com/exec/obidos/ASIN/B0058YPO9A/ref=nosim/happydaysonline3-20

The Complete Third Season
http://www.amazon.com/exec/obidos/ASIN/B00BMEF7TC/ref=nosim/happydaysonline3-20

The Final (Fourth) Season
http://www.amazon.com/exec/obidos/ASIN/B00GGMKSGM/ref=nosim/happydaysonline3-20