Donnie,
Your local building department may have regulations regarding your deck construction, I would check with them first.
Most architects I work with go by the 1/3--2/3 rule. You can safely cantilever 1/3 of the structure,[assuming its properly anchored into the ground] a 16' long deck you could cantilever 5'4". I personally would use treated or redwood/cedar joists at least 2x8 on 16" centers.
Also, if your having a party on the deck you wouldn't want everyone on the cantelever at the same time. Good luck, it will be fun to build.
