I have an Ovation electric/acoustic and I was wondering if anyone could tell me why I'm not getting any sound out of the bottom e string when pluged in? All the other strings pick up perfectly, is there an easy fix or should I take it to the shop?
I think you need to take the strings off, lift off the the saddle and make sure theres no crap underneath. Make sure its flat on the pickup underneath and re-string. It might take a few gos but youl get there!
and also check if the saddle doesn't stick in it's slot. Normally a tight fit is recommended on acoustic guitars, but not when a pick-up is involved. In that case the saddle must be fairly loose in it's slot. Not that loose that it can tilt and spoil intonation, but loose enough that you can lift it out without effort. If it's too tight friction on the sides will absorb vibrations before they can reach the bottom of the slot where the pick-up is.

If all the above checks out alright, you must assume that the piezo strip itself is faulty. Any other malfunction I can think of would affect all the strings, not just one. In that case you could best take it to a guitar tech.