Scholars Portal Books
The starting URL should be "http://books.scholarsportal.info/SolrRequest?raw=true&" and the rest is any parameter compatible with Solr (more about search parameters: http://wiki.apache.org/solr/SearchHandler)
For example:
A simple query with XML response for Titles with "Degas": http://books.scholarsportal.info/SolrRequest?raw=true&q=Title:Degas&start=0&rows=2000&indent=on (maximum rows returned will be limited to 1000)
A fecet query with JSON response: http://books.scholarsportal.info/SolrRequest?raw=true&rows=0&indent=on&facet=true&facet.limit=20&facet.mincount=1&facet.field=LCC1-sortable&facet.field=SubjectLCSH-sortable&facet.field=Contributor-sortable&facet.field=Series-sortable&facet.field=Type-sortable&facet.field=Language-sortable&wt=json&json.wrf=Solr.retrieve&q=Title:Degas
Solr throws an error if an undefined field is used, so make sure to include the correct field names from schema .