Dear jszair
Hi
As i understood , you want design a simple slope change ,detector . i think below circuit can help you . its out put will be a dc voltage at the max amplitude of your sine input.
If voltage changes slowly, then I'd just attenuate/amplify (anyway, condition the signal) and then sample with ADC built into microcontroller.
If you specifically need to design an analog circuit, then it depends what are the frequencies. At some fractions of Hz capacitor leakage current plays significant role.