Newest driver for a laptop is the one provided by the manufacturer. If they stopped supporting it, that's bad luck.
If you really have to have newer drivers, try modding the current generic mobility drivers (available from amd.com). It may or may not work but worth a try if you're up to it. You'll need Notepad and some common sense, and also there are plenty of tutorials on the internet.
CPU: AMD Phenom II X4 810 @ 3250MHz | RAM: Kingmax 2x2GB DDR2 800 @ 833MHz| MoBo: MSI K9A2 CF v1.0 (BIOS: 1.D)| GPU: Asus HD 6850 1024MB (DirectCu) @ 850/1100MHz | Display: Chili Green Vision L24FHD | PSU: PC Power & Cooling Silencer 750 Quad | OS: MS Windows 95 x64 Edition
CPU: Pentium 4 Northwood S478 @ 3200MHz | RAM: 1,5GB DDR 400| MoBo: Gigabyte GA-8S661FXMP-RZ | GPU: Abit Geforce Ti 4200 | Display: Dimarson 19" CRT | PSU: Noname 400W | OS: MS Windows XP Pro, Fedora 18