There are two
marinas near Nadi (pronounced 'nandee' for those of you who haven't been there), Denarau and Vuda (pronounced 'voonda') Point. Denarau is closer to the city of Nadi but is much more like a Southern
California marina. Vuda Point is farther from Nadi and is better protected from
weather but is more rustic.
There is wonderful sailing and exotic, beautiful places to sail not only in the Yasawas but also in the closer Mamanucas. The paper and electronic
charts are terrible, though, and many cruisers rely on
Google Earth for
navigation. If you're into surfing, there's some world-class spots very near Nadi.
I have no knowledge of importing a
boat to Fiiji, sorry. It wouldn't surprise me, though, if you couldn't find a selection of boats in
Fiji for sale.
Fair winds and calm seas.