The 'Snake pickup' from Headway http://headwayelectronics.com is by far the best acoustic pickup I have heard and used, I know they make better more expensive models, but for simplicity and easy of use, use a DI box etc and you have all the control you need.

I have four, two in guitars an done each in a bouzouki and a mandolin, and I have not a bad word to say about them.

Geoff