Based on your original observation of slow cranking, I'd suspect a frayed battery cable to the starter or engine block, or worn contacts inside the starter solenoid. With worn contacts, you should still get a single nice loud clunk when the starter engages, each time you turn the ignition switch to "crank". Testing will show whether the positive battery cable to the starter or the solenoid contacts are at fault.
A frayed or loose negative cable to the engine block can prevent the solenoid from engaging, and since it doesn't turn on to let the starter try to draw heavy current, that could be a little trickier to find with voltmeter tests. You might have to go right to the starter and jump the solenoid terminal to the large battery terminal to get it to try to turn on.
Here's a photo of your starter motor from rockauto. Com. Start by using an inexpensive digital voltmeter to measure between a paint free surface on the engine or starter motor, (green arrow), and the battery terminal on the starter, (red arrow), while a helper turns the ignition switch to "crank". If you find full battery voltage there, near 12.6 volts, all the time, move the voltmeter probe from the battery terminal to the solenoid terminal. You should find battery voltage there in the "crank" position. Check on both of the smaller terminals; I'm not sure which one is the solenoid terminal.
Holler back with what you find for voltages at those points and any sounds you hear from the starter solenoid and starter relay.
Friday, February 24th, 2012 AT 11:14 PM