Advances in virtual education environments have enabled us to optimize the construction process of content through the reuse of learning objects, which are stored in repositories. To ensure interoperability, integration and reusability of learning objects, standards, such as SCORM, have been designed to ensure structural interoperability of learning objects. Additionally, there exists a good number of E-Learning Management Systems (LMS) that let us design content for E-Learning platforms. Most of these systems support the reuse of learning objects that have previously been selected in learning object repositories. Normally, these repositories and the existing LMS operate as two independent systems. As an alternative to integration, we propose in this paper a software architecture based on web services that provides two functionalities: Integration of searches in many learning objects repositories and building and composition of learning objects for E-Learning platforms.