Most of us don't see horses every day. I'm not an artist, but I strongly believe that one of the reasons horses are so difficult to draw is that we all have a primal sense of what horses should look like. It's hard to get all the little details right, but we all know when it looks wrong. The horse-human bond goes back to cave paintings. Even today, artists are still drawn to horses, and often asked to draw horses for various assignments.
If you want to draw horses, study horse behavior. For the animated film "Spirit", the horses were given eyebrows to make their faces more expressive. Since real horses lack eyebrows, they express themselves with their ears and their body language.
Horses are large, but they are prey animals. They are always poised for fight or flight. That's one reason they rarely stand with their weight evenly distributed on all four legs, ears pricked foreword. Horses drawn in this type of pose will always read unnaturally to the viewer. The natural position for a horse in repose is to have one hoof slightly raised, resting on the tip, and one or both ears turned to the side, scanning for sounds. The key is, even at rest, to suggest that the horse is only seconds away from motion. Also, horses can't see directly in front of themselves. Their eyes are too far apart for that. And their nostrils are sensitive and expressive, flaring out when they are frightened or at full gallop.
Even urban areas have places to observe horses. Riding stables usually offer group lessons that can be observed from a viewing area. Horse shows include Western riding events from team penning to barrel racing; English show jumping; and Dressage, the horse version of ballet. Dressage is based on the movements that war horses were taught in ancient times, and are great reference for historical battle scenes. Understanding the different riding disciplines, and how skilled riders are centered riders using cues from their bodies and not just tack and artificial aids to direct their mounts, will all add authenticity to your drawings. Horses walk, trot, canter, gallop and pace. They rear up; they roll on their backs to scratch fly bites; they fight; they nuzzle; they even swim.... understanding horse anatomy in action will improve your rendering of all animals.
And you can even get your own authentic, scale replica horse, in a variety of colors and breeds.
This model horse is a classic Breyer model of an arabian stallion.
Here are some customized model horses:
Okay, maybe I know a little bit too much about all this... but the point is, and... wait for it, it's coming...
A good model horse will cost you about $30, but it's a terrific resource for your studio. Breyer is a great website to start. They've been around forever. They started the whole "model horse show" craze. They produce models in a range of authentic scales, if you're into that sort of thing. And these days, they even list the names of the artists who sculpt their horses. You can buy Breyer horses online or at stores like Toys R Us and JC Penny. Here's the link to the product line at the Breyer website... http://www.breyerhorses.com/products/
And if you always wanted your own real horse, but live in a loft or apartment with only a small balcony, how about a fiberglass horse, (or cow, or whatever) custom painted at 1:1 scale.... http://www.fiberstock.com/stock-animals/fiberglass-horses
In the meantime, start with that broomstick. And keep drawing!!!