Sales with GTD
I own a small company, so I don't have to deal with things like territories, etc., but here is my approach.
I have a sub-projects list entitled Opportunities. I list all open opportunities and review it like any other project list, making sure I have a next action for each. A lot of times the next action will be on the Waiting For list because I have a full-time salesperson. It's easy enough to move an opportunity to my main project list once the job is sold.
I use a separate list in my project reference material that details where each opportunity is in the pipeline and other related info. such as vendor quotes, our quote amount, etc. I also archive any lost and awarded opportunities here.