Nice to meet you, I am new myself to this forum.
I suggest you take up lessons in whichever discipline you'd like to do. Before you purchase a new horse, try leasing one to see how you like it. When you and your instructor feel that you have enough experience, Id start looking around.
Make a list of what you want to see in your horse and how much you could afford to spend. Correct conformation, disposition, breed, height, level of training all are things important to know. Most importantly, be honest with yourself. Don't tell yourself, oh he might work out or he looks nice I like him. No. Don't settle for second best. It'll save you in the long run.
You won't find a horse overnight. I spent 3 years! Looking for my stallion that I now have (he is 2.5 years old now). And I still am having a hard time finding the perfect mares I want (been looking for almost 4 years now :roll: ).