Simon & Schuster, Penguin, Pocketbooks, Kensington & St. Martin's all publish the genre. Erotica/erotic romance imprints have been added to their lineups and those imprints include all subgenres of erotic romance/erotica. Most erotica and romance nowadays is crossgenre. For these you may want to try getting an agent first though.
If you want to try epublishing, Samhain Publishing, Loose Id and Ellora's Cave/Cerridwen Press are good ones to check. For epublishers you can send your own queries. No need for an agent. Just check their submissions guidelines and follow those guidelines to the tee before sending the query. This applies to any publisher, though, even if you get an agent.