I recommend ASUS and Lenovo, good quality, good battery life. Especially the Thinkpad series from Lenovo, because Lenovo bought the IBM PC manufacturer department, and IBM Thinkpads are like... the best laptops ever, for business applications anyways, though they are pretty costly.
ASUS laptops are good all round, design, specs, value, performance, battery life, cost.
Acer/Gateway/E-Machines (3 brands, but they are all really the same company, Acer) laptops are cheap, but they are cheap in material too (my friend's Acer died in less than 2 years, the northbridge fried), and have average battery life. HP/Compaq (again, they are the same company, HP - Hewlett Packard) laptops are decent in design and are fairly inexpensive, but their battery life is only average. Toshiba laptops are decent as well.
I don't know what's considered cheap in America, nor do I know what kind of hardware is needed for SC2, but I'll give a couple of recommendations that I see from Newegg.com:
This looks pretty good
So does this
$950, but great for the price point IMO
Hope this helps a bit.