I listened to some interesting talks about e-publishing yesterday. One speaker had found a publisher who acted much like a traditional publisher. Another had paid for a cover and for proofreading/formatting. A third had done it all himself.
I didn't realise that there's a support industry built around e-writing. If you want editing/graphical/translation services, you can put the task out for tender and get samples and references from free-lancers.
Marketing's a slog, but it's never easy. No one sounded keen about Twitter or even Facebook - not worth the time you need to invest. Fiction Press and Goodreads provided more efficient links. It was suggested that writing more books was the best form of marketing - books sell each other ("If you like this book, you might ...."). Repackage books. Find new markets abroad (France and Germany) or produce an Audio book.
The cover's especially important for online sales (it has to look good when shrunk). Even if you do it yourself, you may well have to pay for artwork.