Google-owned YouTube hasn’t had a serious competitor for years. But Yahoo would like to try: The Web giant has been working on a plan to lure some of YouTube’s most popular stars and networks to show their stuff on the site, according to several sources close to the situation. The strategy in the works — which Yahoo hopes to launch in the next few months — is aimed at taking advantage of persistent complaints by both video creators and owners, who think that they don’t make enough money on YouTube. Yahoo CEO Marissa Mayer has been mulling how to have a much bigger presence in Web video. Under her leadership, the company tried and failed to buy France’s DailyMotion and has been pushing a number of other high-profile media initiatives, such as adding television news star Katie Couric to its site.