Thank you Mitch!
I'm new to DNN and have limited programming experience (actually, the last programming I did was assembly code for an embedded processor :-) I would like a solution that doesn't require any programming customization, if possible, but I don't know enough about DNN and the available modules to visualize the implementation details that are necessary to be more specific. Kind of a catch 22 :-(
On a functional level, I can provide this example:
Martha Smith logs into the site, excited to let the community know about a new tool that she has seen. A page on the site contains fields that allow Martha to enter various info about the tool (name, description, length, height, price, comments, etc.)--these field correspond to a db row. Other users can view all the tools in the db on another page, or search on the basis of any field. If a user finds an error, an abuse, or wants to add more info about a tool, s/he clicks on the corresponding link.
George