So if you need information about SAT Subject Test requirements, here is the best place I've found to start. The folks over at Compass Education Group have researched which schools require the SAT Subject Tests (formerly called the SAT-IIs) and shared everything they've found here.
Of course, you should always check with the individual colleges (as you should with any admissions policy). But Compass makes that easy by giving you the link to each of the colleges' websites where you can find this information.