There is an array of solutions for this particular problem. First, one of the cheapest and easiest ways to correct this problem is to look for circulation. Take off the radiator cap while the engine is cool, start the engine and look at two things, the coolant level and the circulation. If the circulation is extremely poor and the coolant level is "normal" to "high", then chances are either the radiator is clogged or the water pump is bad. Next, with the radiator cap still off, bring the RPM's to around 2000-2500 and if circulation does not improve or if the coolant level does not decrease then i'd bet you have a clogged radiator. To determine bad pump from clog, turn off the engine after it has gotten to about 215-220 degrees Fahrenheit, underneath the vehicle on the bottom of the radiator, there is a release plug similar to an oil pan release plug. Turn the plug counterclockwise until coolant begins to leak, If the coolant on the bottom of the radiator is significantly cooler than the coolant on the top, then its a clog, if the two are the same temperature or very close, then its the water pump. To cure the clog, flush the radiator and if its the pump then replace the pump, however consult your repair manual for both procedures.