These have their own websites, where you can find everything you need.
SANE (Scanner Access Now Easy) package, offers the suppport for scanners. It can be downloaded from ftp://ftp.mostang.com/pub/sane. Documentation are avaliable at SANE webpage, where you can also find several frontends and backends.
Today at The Linux Wacom Project website there are useful tools to manage a Wacom pen tablet: drivers, libraries, documentation for configuring and getting it running. Not only but also diagnostic applications and of course mailing lists and FAQ. This website is maintained by John E. Joganic <jej@j-arkadia.com>