Celerons are really slow and dated CPUs. For about $300, you should be able to get an AMD A6 or Intel Core i3 laptop. Here are a few options from Best Buy:
1. HP - 15.6" Laptop - AMD A6-Series - 4GB Memory - 500GB Hard Drive - Black Model: 15-f305dxSKU: 4221508 $270.99
2. HP - 15.6" Laptop - AMD A6-Series - 4GB Memory - 500GB Hard Drive - Black Model: 15-af131dxSKU: 4481400 $279.99
3. Asus - X Series 15.6" Laptop - Intel Core i3 - 4GB Memory - 500GB Hard Drive - Black Model: X555LADH31WXSKU: 4569209 $329.99
4. Lenovo - 15.6" Laptop - Intel Core i3 - 4GB Memory - 1TB Hard Drive - Black Model: G50 - 80L000H2USSKU: 9679149 $329.99