The days when you had to resample artwork before sending it to the printer are looooooooooong since past. The only exception is if your source image is very low resolution, and even then some printer drivers do a better job than Photoshop at upscaling.
If your image is at least 150 ppi at final output size, just print it. If it's above 85 ppi, just print it but be prepared to discard the print and do some experimenting. If it's less than that...well, either you're printing a billboard and you know what you're doing, or you're a lost cause.
Of much more importance to the print quality is your sharpening workflow. That's beyond the scope of a forum post, but an excellent place to start is by viewing the picture at actual size (by holding a physical ruler up to the onscreen ruler and adjusting the magnification until they match) and then sharpening it until you like the way it looks. You'll probably overshot the mark a bit, but it's a quick way to get it into the ballpark and it may well be "good enough" for your porpoises.
Cheers,
b&
