It's very simple, and clearly I can attest that it works. Generally it is images, not HTML, that require a lot of server space, though if you keep your image file size relatively small, 50k or smaller, not only can you put up more images but site visitors will be more likely to wait to see your images. I know I have. This is important to bear in mind when you're putting images on your site, and I recommend not putting too many on a single page. Scanners nowadays are pretty cheap a lot of manufacturers started throwing them in for free with the purchase of a computer.
Digital cameras are also now pretty cheap, and they work really well.
For web use, you really don't need the ones with the most megapixels while this may be necessary if you want to create digital images for printing, these file sizes are too large to use on the web. However, if you're going to invest, I recommend getting the best one that you can afford and then using a lower setting for images intended for the web. If you can't afford or do not have access to either of these options, you can investigate cheaper alternatives to getting your images digitized. Seattle Filmworks is a company that will process your film and return it as digital files, but most commercial processing places will do that nowadays for a nominal additional fee. Watch for specials because it is increasingly popular, some outfits will throw it in for free with your regular processing.