Where are any links on how to make brush presets for zbrush?
What do you mean by brush presets? If you want to create a custom brush all you need to do is adjust the settings you want in the Brush palette and the Stroke palette, and assign an alpha of you choice. Then save the custom Brush using the Save button at the top of the Brush palette. If you save the Brush to the ZStartup/BrushPresets folder then it will be avalable each time you launch Brush.
You can also create selection or masking custom brushes. Just make sure you hold Shift+Ctrl (for selection) or Ctrl (for masking) while you make the adjustments.