Who do we talk to about preparing an information memorandum before a financing round?

The basic answer is all the delegalised and non-sensitive outlines. The SEC has very strict rules on what needs to be prepared to whom and one requirement is a qualified investor whereas the IM (so long as not making promises or solicitating) is more an intro, think teaser ad to movie.

Any decent securities lawyer preparing your PPM can advise what needs to be left out.