You can find it in ftp://ftp.kde.org/pub/kde/stable/kdepim-4.6.1/src

You'll need both kdepim and kdepim-runtime, and please make sure to have the most recent Akonadi, Soprano, kdelibs4, kdepimlibs4.6 and friends.

Also shared-desktop-ontologies (SDO) 0.6.x is required -- kdepim 4.6.1 will not build against newer versions of SDO.

See the list of bugs we fixed since 4.6.0.

I don't know yet if we'll make 4.6.2 release, as KDE SC 4.7 is fast approaching.