Need Suggestions

It is always 'What should I buy?'

So here is what I am looking for:

screen size: 11"-14"
os: linux (only and only linux)
mobility: yes
ram: 4+G (necessity, need to be running database)
hdd: 250/320 G, but looking at price wars - 500 G
life: 4-5 yrs even an expectancy of 3 would do
processor: need advice on AMD and INTEL
brand: not much of like or dislike, its upto availability

That's the minimum, and that would be all I would be needing of it.
With the above being said, I'm not hoping to shoot through a budget.
I'm really confused.
Can't even pick 5-10 of them and choose out of it.
I need some real good input here.