Welcome to large format photography! I hope that you'll enjoy it as much as the rest of us seem to.
View camera lensboards have holes in the middle for the lens to fit through. Most large format cameras don't have built-in shutters, instead each lens comes with its own shutter. Copal is the most common brand of shutter, and I believe the only one still in production. Common older brands of shutters included Compur, Ilex, Seiko, etc. Shutters came in sizes from "00", "0", "1", "2", "3", "4" and "5"; the larger the number the bigger the shutter, and generally the larger sized hole through the lensboard required. Many of these sizes are obsolete: only sizes "0", "1" and "3" are still made, as far as I know. Other sizes may be encountered on older used lenses.
Lensboards themselves are usually pretty simple, either a flat piece of wood, metal, or plastic or two flat pieces, the inner one slightly smaller than the outer one in order to make a light trap when fitted into the camera. The manufacturer of your camera will sell you lensboards, as will any number of other retailers, mail order dealers, and people who specialize in that sort of thing. Or you can make your own: they're really very simple to make. Sometimes lensboards from one brand of camera will fit other brands: Linhof/Technika lensboards, for example, are something of an unofficial standard and fit several brands of camera.
A pretty common range of lenses for your kind of camera would be 90mm, 150mm, and 210mm. If I recall rightly, your camera can extend out to about 12" (300mm) or so; this limits the focal length of the lenses you'll be able to use with it. 210mm to 240mm will be about as long as it can handle and still be able to focus closer than infinity; a 300mm lens might be able to focus down to 20 feet or so, but probably not much closer. Telephoto lenses require less bellows extension in order to focus and you could probably use a somewhat longer lens of that design, but there are disadvantages to that design and they're going to be rather expensive. In any case, common practice is to have a lensboard for each lens you have, so that you don't have to swap lenses between lensboards in the field. Older lenses screwed into a flange which was itself screwed to the front of the lensboard; newer lenses have a thin metal ring, a nut if you will, which screws onto the back of the lens and holds it tight against the lensboard. You often have to unscrew the len's rear element to fit the lens to the lensboard, then screw the rear element back on when you've finished mounting the lens. This leaves the delicate shutter mechanism exposed and care is reqiured as the exposed bits are easy to damage and expensive to repair. This is also why most of us don't want to have to mess with changing out lensboards in the field.

Thus, the procedure is to decide on the lens (so that you know what size the shutter will be,) before you make or buy the lensboard. That said, if you have a lensboard with a hole for a Copal 0 or 1 shutter go ahead and keep it because almost all of us have at least one lens with this size shutter: they are by far the most common.
If you can find a copy, get Steve Simmons' book on using large format cameras ("view cameras") and you might also find useful information at his web site,
www.viewcamera.com. His book is the best I've found for beginners and was very helpful to me when I was starting out. His magazine is also pretty interesting.
Mike