I find browsing is better on the publishers' websites than on the retailers', they are not clogged up with mountains of public-domain and self-published crap, and choosing one that publishes the type of books I like greatly narrows down the selection and makes browsing manageable. Most of them have a way to browse authors alphabetically.
Apart from publisher sites themselves, another one I think is great for browsing is
The Encyclopedia of Science Fiction, as well as
author it can also be browsed by
theme, and has some good critical articles on the authors..