HP Officejet 4500 All-in-One inkjet & network Printer (G510g)
Support page:
http://h10025.www1.hp.com/ewfrf/wc/product?product=3919449&lc=en&cc=us&dlc=en&lang=en&cc=us
Windows 7 64-bit installation (self-extracting zip file executables):
http://ftp.hp.com/pub/softlib/software11/COL32438/mp-80344-1/OJ4500vG510g-m_Full_13_en.exe (HP.com download) (223.45M)
HP All-in-One Printer Drivers - Full Feature (229 MB) (hosted space download)
You want the full install over the basic, in order to take full advantage of the scanner features (ie., OCR).