edit ~/.Xdefaults and add these lines:
Xcursor.theme=<themename>
Xcursor.size=16|24|32|48|64
There's a lot of themes on
KDE-Look's XFree cursor section (see side panel). Unpack the theme to ~/.icons
(it will be a directory of the theme name).
If the theme has a Makefile file in it, you should unpack it then run it, it will probably generate the cursor files and make symlinks for QT (I believe it still needs symlinks, anyone correct me if I'm wrong).
themes.freshmeat.net has some Xfree cursor projects too I think. As for tools, KDE chose not to provide tools becuase they think it's all a mess (ehk), but I'm not sure about GNOME or Redhat.