Most Linux websites I regularly visited features new icon and gtk themes every few weeks, but I’ve never seen them show any cursor themes. Maybe it also has to do with the fact that
Cursor theme is one of Linux’s customization aspects that is often overlooked, but it can give some refreshing detail to your desktop. Besides aesthetic purposes, changing your cursor theme, especially to a color other than black/white, can also help if you want to keep your cursor highly visible at all times. If you’re a left-handed person and regular, top-left facing cursor feels awkward to you, some cursor themes also have left-handed versions.
You can download new cursor themes from Ubuntu’s repository (search for cursor-theme) and from sites like Gnome-Look. If you do the latter, you can extract the files to either /usr/share/icons or ./.icons.
On Xfce, you can change cursors on the Mouse and Touchpad options (instead of Appearance, which confused me for a while), while on MATE, it’s on Appearance>Custom>Cursors.
Here are several cursor themes that I like. All themes in this list, except for pixelfun3 and Ghost, are available in multiple colors.
Available from Gnome Look and PPA:
sudo apt-get install comixcursors-righthanded comixcursors-righthanded-opaque
sudo apt-get install comixcursors-lefthanded comixcursors-lefthanded -opaque