Electromagnetic levitation systems bring unique benefits to many fields of industry. In this context, feedback control is challenging as, in practice, only the position of the levitating object and the electromagnet current can be measured. Since we need to know all the system's state variables, including the levitating object's velocity, to ensure effective position tracking, we address the problem of constructing state observers. More specifically, we investigate a feedback linearization control scheme and design observers for output feedback by relying just on measurements of position and current. We find the observer gain by solving problems based on LMIs (linear matrix inequalities) and test our approach in simulation. The results confirm the advantage of using this control scheme with a properly selected observer gain, while considering the disturbances acting on the system.