ltspice is free, but you have to define what you mean by components? Like various different IC's? You generally don't try to simulate them all in one go, you modularize the various circuit stages you're testing and simulate each stage independently, using the input or output from one stage to feed the next as it's behavior is characterized. More detail about the circuit you're trying to simulate, the components involved and exactly what you're trying to achieve would be nice. You could start with what kind of output the switches you're using produce. Because if it's truly analog (touch sensitive) then you're not talking about a switch per say.