There are special Search Engines that are specialized on Linked Data. The oldest one is Swoogle which is a keyword-based Search Engine based on Apache-Lucene that uses only limited Semantic Annotations.
With those Search Engines one can simple look up a word and then it looks up are there Resources in the Linked Data Cloud that are related to the Query. Then one can select certain Datasets, certain Ontologies or certain Entities that one can use for Applications. For these kind of purposes one can use these Search Engines that are specialized on Linked Data.