The tutorial on the ThemeForest blog worked when I tried it awhile back. Try this tutorial: how-to-create-a-theme-options-page-for-your-wordpress-theme This seems to be the most standard way to create options. The only issue I see with this method is that every single option adds one database entry. consolidate-options-with-arrays-in-your-wordpress-themes/
I think ThemeForest’s article is only compatible with whatever version of Wordpress there was at the time.
If I were you, I’d take a look at basic theme options from free themes – those are as basic as it gets. Try to look at 3-4 themes, they all add different options.
Then, since you’ve already read tuts on this, try to inspire yourself and do a basic one similar to those of the free themes – just for testing.
I’m doing that myself now – I think it’s an easier and fun way of learning.
Finally, I don’t get it – why is this such a well kept secret? I mean, all other stuff is shared through tutorials and the like, only this stays on the low-low.
What is this? KGB ? 
