Here is a general link from the Reciprocity website which may be of some help - you can navigate through to course catalogues and course schedules (current) for each campus: Reciprocal Exchanges
Berkeley: Courses by department http://sis.berkeley.edu/gc/curricula.html (Within each department, you will want to go to the link for 'Related Course Descriptions'. There are also links to departmental pages here.)
Davis: Courses by department http://registrar.ucdavis.edu/UCDWebCatalog/programs.html Again, clicking on the department listed will then take you to a page where you can view course descriptions and link to the departmental website.
Irvine: Courses by School (Faculty) http://www.editor.uci.edu/catalogue/ (Scroll down to the heading labelled 'Schools, Departments and Programs', then click the School of choice. This will take you to a new page where you can select a department, and finally the course choices).
Los Angeles: Course Descriptions by Department http://www.registrar.ucla.edu/schedule/catsel.aspx This one is fairly straightforward.
Riverside: this is a pdf file: http://www.catalog.ucr.edu
San Diego: Courses, curricula and programs of Instruction: http://www.ucsd.edu/catalog/front/courses.html You can see the departments listed, and can simply click 'courses' alongside any of the departments to view offerings.
The Times Higher Education Supplement world ranking lists the following UC campuses in their top 200:
UC Berkeley at Number 3
UCLA at Number 41
UC San Diego at Number 58 (just below Warwick at Number 57!)
UC Davis at Number 96
UC Santa Barbara at Number 117
UC Irvine at Number 140