Thank you, WGN, for posting that specific link. Thank you, to the OP, for a question almost exactly like mine.
That link to Ubuntu's certified products is EXACTLY what I need right now. I've been going a little batty trying to figure out which of the least expensive NEW laptops would work with Ubuntu or Mint. Thank you a million. My budget will likely be under $400 - and if I could find one for far less that would be better.
Have been running Linux Mint Maya (13) XFCE on an old Thinkpad R51. It is strong enough to do most of what I need, even in my graphic design work, but it could use a little more oomph. It falls seriously short, however, in the way youtube videos and some intensive websites serious tax its processors and make it get really hot (even with additional cooling fans.) Have been trying to figure out how much I'd need to save up for a new laptop so that my R51 can be my backup system - and leave some cash for a separate monitor. Am interested in dual booting with Windows to take advantage of some software I can't get for Linux. Although I love my old decades of using Apple, Macs are now ridiculously above my head on price. If I could dual boot Linux to Windows, I'd be getting everything I need: 80% Linux and maybe 20% windows apps.
By the way, when I searched for Linux laptops on Amazon, they came up with a few offerings, if that is of any help to anyone. I'll be searching the certified info on Ubuntu for details.
Thanks again for this excellent discussion.