1. Buy a ton of domains 2. Put up picture-based landing pages on those domains. The user only really sees pictures. 3. Put up or spin content with relevant keywords, put it underneath the images. Google only sees a couple pictures (it doesn't know what they are) and a bunch of really relevant content. 4. Build a shiz-ton of links. This is where black hatters really make their money. I usually build about 125,000 links/day from completely legit sites, and to Google it pretty much looks like it's going viral. If you know where to get the links, know how to generate the content, and can make them seem human, Google has a really hard time finding you. 5. Link the landing pages to your money site using affiliate links. 6. Wait until your site gets manually reviewed and pulled down.
So any somewhat decent black-hatter will have hundreds of sites in the works at any given time. The worry of taking a site down isn't a big one, even though if you take down one site a black-hatter's traffic could drop 3,000 visits/day. The sites I work on usually remain up for an average of 6 months at a time, and the only way for them to be caught is a manual review. Some only stay up for a couple weeks, but some stay up for years. There have been times when landing pages are getting a couple thousand visits a day but I haven't had time to go back through and redirect the traffic to the money site or update them from the generic landing page.
Since all of the actions taken mimic closely enough what humans would do, it's really difficult to be caught by webspam teams.