Jupiter is around 50 arcseconds visually, Neptune only about 2.2 arcseconds. With a 9mm EP and assuming 1000mm aperture focal length, this will give a power of 111. At this power, you aren't going to resolve a disk for Neptune but, at magnitude 8, you should certainly see it. Distinguishing it from the surrounding stars is not easy- you need a map.
http://www.skyandtelescope.com/obser.../41561382.html
Regards, Rob