YOU MAY COUNT YOURSELF AMONG THE MASSES OF MARKETING, advertising and PR pros who are constantly trying to get a grip on new media. On the flip side, you may be a marketing or creative type who is trying to get your ideas into the right hands. Now there's a place for both precincts: NuIdeaExchange.com. The Web site, which went live this month, unites companies, marketing and media professionals, as well as the public at large, in order to buy and sell ideas. The Web site divides its users into two distinct groups: seekers and thinkers. Seekers are companies with marketing/advertising needs that are looking for ideas. Thinkers are marketing/advertising professionals and nonprofessionals who are selling their ideas to seekers. Seekers are able to access ideas for a specific marketing challenge or assignment. In turn, thinkers can pick and choose from a wide variety of assignments and opportunities, and evaluate the companies presenting the opportunity before committing to the project.