OntoSelect is a dynamic web-based ontology library that harvests, analyzes and organizes ontologies published on the Semantic Web. OntoSelect allows searching as well as browsing of ontologies according to size (number of classes, properties), representation format (DAML, RDFS, OWL), connectedness (score over the number of included and referring ontologies) and human languages used for class- and object property-labels. Ontology search in OntoSelect is based on a combined measure of coverage, structure and connectedness. Further, and in contrast to other ontology search engines, OntoSelect provides ontology search based on a complete web document instead of one or more keywords only.