There is considerable interest in nightscapes with digital cameras. Four recent eBooks on this subject are quite good. They are:
Royce Bair, A Guide to Photographing the Starry Night Sky, Milky Way Nightscapes, 140 page pdf eBook, $19.99 USD.
Grant Collier, Collier’s Guide to Night Photography in the Great Outdoors, 160 page pdf eBook, $18.95 USD. Also available with video ($72.95) and in signed paperback ($29.95).
Phil Hart, Shooting Stars, 129 page pdf eBook, $19.95 USD.
David Kingham, NIGHTSCAPE, A Complete Guide to Photographing Under the Night Sky, 120 page pdf eBook , $12.00 CD.
These books are reviewed on my photography Blog. Take a look at:
photophys.com