Please help?

Hello,I've just recently installed Drupal ( a few days ago) and is very new to it so I am really confused. The help on this forum is amazing. I am wondering if anyone can help me. I am trying to create a section on my site that allows members who are advertisers to log in and post ads. I want them to be able to do two things, post an ad that takes up an entire page and that allows html and links and which will hopefully be paid (so they'll have a page of advertising space), and I also want them to be able to log in and post like a short yellow page ad, one that only takes address, website, and a couple lines (like a yellow pages directory). This they can do for free. Then I want members who are users or even non members to be able to search based on category, and search for the ads, well they would just be searching for a vendor, or a service but searching will bring up the pages (ads) that were posted by the advertisers. Drupal seems so complex It seems like this function would exist in some module, however it seems like it will take me literally months to get to this point. Any help at all will be completely appreciated. Thanks !