Buying each separately at their best prices online is $60
Today GameFly launched a new Borderlands Collection for PC Download. It includes Borderlands 2 and the Borderlands Game of the Year Edition. After $30 instant savings and coupon code "GFDMAR20" the price is down to $23.99.
Borderlands Collection - Borderlands GOTY + Borderlands 2 (PC Download) — $23.99 at GameFly.
The cheapest you can buy these two games separately online is Borderlands 2 for $45 and Borderlands GOTY for $15 at Amazon. GameFly's offer is $35 cheaper.