I heartily recommend ENTREZ as well. It contains both DNA and
protein seq. databases, relevant Medline references, and a nice
software interface for searching. It is also the best software
bargain I've seen-- updates regularly on CD-ROM at a minimal cost.
It has replaced much of my e-mail searching of Genbank excepting for
the latest "updated" sequences since the last release of ENTREZ.
Another amazing bargain from the folks at NCBI is the MACAW program
for finding local sequence homologies. You can spend a lot more
money (especially since MACAW is free, or at least already paid for
by your tax dollars), and won't do better elsewhere.
Joe Lipsick <Joseph.Lipsick at Forsythe.Stanford.edu>
P.S. The US government publications office which handles ENTREZ
distribution is not the most user-friendly organization. Be
persistent. Fortunately, once you're on the mailing list it's easy
to stay on.