I have a question about buying webspace for the creation of a .com website. Many companies offer "rental" for under $10 / year, but is there a good option that is more permanent? What's involved in launching your own .com website?

You need two things. Most hosting companies offer both but I recommend you to kep them at separate companies:

1) A domain name. That's around $10,- a year. Usually less. Take a look at GoDaddy or 1and1.

2) A hosting solution. They come as cheap as a dollar a month (1portfolio), through regular/large packages (iPowerWeb, $7,95 a month) to getting your own server (LayeredTech, starting at $56 or so).

The reason to keep your hosting and domain name at separate companies is because it makes it much easier to switch hosting if you outgrow your current hosting plan. You can get free hosting as well, but paid solutions are usually far better.