You could scale up a pic to fill the whole area of a page from a screen sized image, but the quality goes down. If you want the image to look good, you'll have to render it for print. Render to disk has the option to set up a dpi... Or multiply the dpi by the number of inches on each side you'll be using for the dimensions of an image. Then take those numbers and set them as the dimensions to use (8x300=2400, and 10x300=3000). You'll only see a portion on screen at a given time, but this way you'll be able to stop and save and restart a render that's partially completed. The image will probably read 72dpi when imported into a 2D program, but you should be able to change the dpi setting. A normal screen sized bryce render at 72dpi will end up filling only part of the printed page if increased to 300dpi. A render that's made for print (too big to view on screen) and has the dpi set to 300 should fill the page nicely. Think of each pixel as being equal to a dot... Note that when increasing dimensions like this that rendering time goes up proportionally. Be prepared to have a computer tied up for at least a whole day when rendering for print.

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Barbequed Pixels?

Your friendly neighborhood Wings3D nut.
Also feel free to browse my freebies at ShareCG.
There might be something worth downloading.