If you went for a much older version (something like 6.x or earlier, maybe 7.x) you might be able to illegally install a working copy if you acquired someone's CD with license key. I think in the more modern era, though, you have to obtain a key online from Apogee, non transferrable, so even if someone wanted to sell you their copy you would not be able to unlock it.
Try forming a TARC team--you can get a copy for $50 if you're young enough or have young friends...
--Chan Stevens