A rabbet plane is not necessary to create a rabbet. If, however, you use a shoulder plane or rabbet block plane without content you shall not conclude that making this feature by hand is tedious or inaccurate.
On June 7th and 8th I will be teaching a class on making a rabbet plane at Lie-Nielsen. In this class you will learn how to make mortises by hand using floats, how to fit a wedge and how to bed an iron, among many other things. All of these skills are directly relatable to successfully making side escapement planes and others. The tool list is too.
I imagine this class as a perfect supplement to Larry Williams' dvd on making side escapement planes. This class will be a hands on experience using the same tools (i.e. floats) while making a plane that compliments side escapement planes perfectly.
I previously posted in regards to making a rabbet plane. Come to Maine and try it out. The process is time consuming, but straight forward.
As a side note, I made this video back when I first started the blog. It's still relevant.
If you don't like the production quality, you can check out my new dvd.