Do I need a clean slate?

A few years ago I did some experimentation with SEO. I had a little success in Google for some specifically targeted search terms, but I did a little experimentation that Google didn't like. Specifically, I redirected my site that was ranking well to go directly to the ebook I was using it to sell, and as soon as Google caught this my site was removed from the search results.

Now I want to start working in SEO as a professional who plays by the rules. The problem is that the site I experimented with was connected to my Google account and had Adsense ads running on it. Do you think Google has identified me as a trickster and will limit the success any websites connected to my current Google Webmaster Tools or Adsense account can reach? That is my fear.

I have considered starting with a clean slate, getting a new computer, and opening a new Webmaster Tools account. The problem is that I couldn't open a new Adsense account because it's connected to my social security number. Do I really need a clean slate? Once a website has been punished for something Google doesn't like, do all websites associated with the same Webmaster Tools and Adsense accounts suffer, or am I worrying about nothing?

I really want to make a career out of SEO but it would seem to be a waste of effort to promote websites that will never successfully rank because Google has attached a stigma to their associated Webmaster Tools and Adsense accounts.