What type of publishing agencies and why?
If you're looking for somewhere to submit a completed manuscript, you probably won't find a publisher who will take an unsolicited manuscript. Credible traditional publishers will only look at manuscripts which are sent to them by a literary agent. If you want to go the traditional route, you'll have to search for an agent who will represent you. If that's your goal, you can start looking at agents and what they'll accept at http://aaronline.org/Find .
If you're interested in self-publishing a book, there's a list available from Wikipedia at http://www.ask.com/wiki/List_of_self-publishing_co... . If you're thinking about self-publishing I suggest using CreateSpace. That's who I use and I'm very happy with the ease of the process.
I hope the links work for you.