Amazon.com has the Corsair 8 GB DDR3 Laptop Memory Kit CMSO8GX3M2A1333C9 for a good price.

Item has a rating of 4.5/5.0 from 142 reviews

Google Products Price : $56.74 ~ $107.76 Shipped

1. Amazon Price : $54.99 Shipped
(Make sure you buy from Amazon, it could be on the right side under "More Buying Choices")

2. Rebate Price : -$10.00 ( Exp : 7/31/11 )

Final Price : $44.99 Shipped After Rebate