To my knowledge, there is no website with Sunday Open Home listings for the Berkeley/Oakland area that is nearly as complete as the Sunday's San Francisco Chronicle Real Estate Section Open Home Guide. Even the Chronicle's own website, sfgate.com, is less complete. You can use the links below, to get an idea of some of the coming (or past) Sunday's open homes. On Sunday, use the paper.

The first two links take you to sfgate.com. On that site, near the lower left of the screen below the words "Search Classifieds," is a little window where you can select which day's edition to search. Pick the Sunday edition. (This may not be available as a choice until mid- or late-afternoon on Saturday).

The other website, homebuyerstour.com, is likely to have fewer homes listed, but the the site has a convenient search capability that allows you to screen the results using a variety of criteria. As agents may add listings here at any time, it's best to wait until at least Saturday to check on Sunday's open homes.

Again, on Sunday, use the paper.

sfgate.com:
For Alameda County (Albany, Berkeley, Oakland, Piedmont, Emeryville…) click here.
For Contra Costa County (Kensington, El Cerrito, Richmond...) click here.

For homebuyerstour.com, click here

Again, use the paper on Sunday.