Water Pump

Thermostats oand head gaskets don't really make noise. I think it's more likely your alternator or water pump bearings are failing. It's also possible it could be the power steering pump low on fluid. Engine off, check the power steering fluid, the level should be between the marks on the dipstick under the filler cap. With the engine running, you could listen under the hood for the noise. Be careful, don't stick your fingers into any moving parts, keep loose hair and clothing out of the way too. Auto Zone stores usually do free diagnostic checks. Get someone to look at it for you. Don't be afraid to go to a shop instead of an auto parts store and ask them what's wrong and how much to fix it. Here's a directory link for you: http://repairpal.com/saturn-repair-in-sparks-nevada