Wanna upgrade my ride

I just purchased a 92 civic cx hatch....it has a and was wondering what should i do for an engine. i currently have a d15b8 engine...and it suckz.
i was thinking of getting a d15z1 or d16z6 but don't know where to begin to get one that fits my budget. saw some on ebay...are there any questions that i should ask the seller. are these engine bolt on and go or do i need other parts to get it working.

The D16Z6 is straight drop in, except for wiring it for VTEC. I would swap that engine in if a B-series engine is not one of your options