Search form or sitemap?
Finding specific content on a complex website is hard. Users spend much time on it, while designers try to facilitate their experience—through clear hierarchical navigation, breadcrumbs, headings and other techniques. But sites having thousands of pages need a more direct approach.
Search forms must be evident and instantly useful, so that the user feels invited to use them. Some web designers place them around meaningless content, which makes them less visible, usable and context-appropriate.
Search forms and sitemaps can be used both to complement each other—with the former placed on the top and the latter on the bottom of the page. The better a search engine is, the less a sitemap is needed.