Join Kristina Sherk from Shark Pixel for an entire class dedicated to teaching you the best methods for retouching eyes using Photoshop. The eyes are the windows to the soul, and the first things viewers connect with when looking at your photographs. Correctly retouching eyes, without going overboard, is one of the most crucial aspects of portrait retouching, and can make or break a photo.

Phlearn Pro - Master Retouching Eyes
https://phlearn.com/tutorial/master-retouching-eyes/
What makes a portrait great? Is it the lighting? The use of color? Beautiful skin, hair, or wardrobe? While all of these things can help create a more powerful image, we think the best portraits emphasize our most important feature. Eyes!

This tutorial shows you how to do realistic retouch eyes.
You will learn how
• to whiten the sclera (whites) of the eye while retaining a natural look;
• to create eyelashes;
• to refresh the eye shadow;
• make the iris eye more expressive.

EYES - 28 Zbrush VDM creature eyes + 15 Eyeballs IMM brush

http://www.artstation.com/marketplace/p/RyvN/eyes-28-zbrush-vdm-creature-eyes-15-eyeballs-imm-brush

28 ZBrush VDM eye brushes (with 2 variations for each : with eyeball and without) + 15 insert mesh eyeballs complete kit.
Another great springboard for ideas - quickly spice up 3D sculpting/designing/concepting, or even augment and change existing sculpts. Included is a Zbrush VDM brush housing all of the 28 eye variations, and a complimentary ZBrush InsertMultiMesh brush with 15 detailed eyeballs.

  Jumpstart your retouching journey with this in-depth practical course tailored to true beginners, aspiring retouchers, working photographers, makeup artists, or anyone looking to upgrade their online presence in the beauty, fashion or wellness industries.  Learn the nuts and bolts of retouching using a non-destructive approach taught in a digestible, accessible way — no experience necessary.  We’ve gathered the most impactful information to jumpstart your learning — and left out the fluff — so you can focus on what’s important and practice in real-time to speed up your progress. Each module offers the essential key topics, complete with video lessons, practice files, bonus materials, practical assignments as well as reading lessons that will allow you to integrate the newfound knowledge through multiple learning modalities.  Understanding, practicing, and perfecting retouching fundamentals will help you form good habits and step into the retouching world as a capable and confident professional.