The only way to truly gain height (Assuming that you have stopped growing. An x-ray of your growth plates is the only way to determine that, although at age 30 it is extremely likely.) is for very expensive, painful and long recovery surgery.
Basically they saw your bone in half, use a frame to suspend the bones a bit apart from each other and let the bone "fill in" the gap. This costs anywhere from $25-100,000 US, requires a 6-9 month rehab process and might get you an inch. Maybe.
My advice would be to make peace with yourself, realize that your height is not abnormal and concentrate on making everything that you have look good.