What is a good place where I can participate in clinical trials?

I am looking for places where I can participate in a science study for money but I do not know of any places that can allow me to do just that. I am looking for places where I can make some money to pay some laptop repairs and some computer parts I need. I am just looking for places where I can participate in experiments for a hefty sum of money but I would also like to work from home if that is possible or at least near my house.