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In reply to both questions, xdirectory is the best yellow pages type module I have been able to find for Xoops. However, it will have to be extensively tweaked to do what you want beyond the basics. It would be nice if it handled things like accepting payment for premium listings as well as some of the other things asked about --but it doesn't.
Do a search on "yellow page" here and look for a thread that links to an example site using xdirectory. That site owner modified the code pretty extensively and did a good job.