Did you watch "Star Trek:Nemesis"? If so, I can refer you to an in-the- following-order list from there, both long version and short version. If you're really serious about getting re-involved in Trek Literature, you definitely need such a list, because recent in-universe events are beginning to tie a lot of things together and lead up to some big upcoming changes, and if you don't follow a certain chronological order you will still enjoy the books, but you will get a "what-the-frack?" sensation when one book refers to events in another that you may not have read. The authors, which cooperate with each other very well, do a good job of presenting things in sort of a "last time, in the Trek literary universe..." way in a few paragraphs, but to get the full effect and feel in-the-know, follow the list order. Off the top of my head I can't think of the full and in-order long and short lists, but I'm sure someone will post them, and I'll try to remember to get back to this when I have it down and give titles and authors and chronological order if someone hasn't beaten me to it.
For the short, short list, the wanna-get-up-to-speed-right-now list, see the last paragraph.
If you're not really hep on the Next Generation crew, I highly recommend both of the Myriad Universe trade paperbacks, each of which has three roughly 150-page stories that take place in alternate universes, kind of a "What If?" of Trek, like (to simplify, and in no particular order) "What if Spock had died as a child and Kirk had to go through TOS and the first few movie adventures with a different first officer?", and "What if Khan had won the Eugenics Wars?, as well as "What if Voyager was crippled and forced to remain in the Delta Quadrant?" If you dig those two books, a third Myriad Universe release will be coming out "soon".
The Vanguard series takes place during the Original Series timeframe and is up to, what, 3-4 books by now? Help me out, people. I own three of the books, but sad to say I have not taken the time to read them yet, but hear they are very, very good.
The Titan series, I can say, is exceptional. They are up to five books now and keep getting better. This series chronicles the adventures of Will Riker and Deanna Troi and assorted characters on the Starship Titan, the command given to Riker after "Star Trek:Nemesis".
There are several Starfleet Corps of Engineers, or SCE for short, but not sure how many books in the series thus far. I have only read the first two, but they're pretty good.
The New Frontier series is up to some sixteen or seventeen books by now and isn't too bad. Again, own most of them, have only read the first six. So many books, so little time.
If Voyager was your thing, the relaunch order is "Homecoming", followed by "The Farther Shore", then "Spirit Walk 1 and 2", and ending thus far with "Full Circle". Reading "Full Circle" alone will catch you up with Voyager, but involves many of the events described in the earlier books, as well as involvement in the "Destiny" trilogy, which encompassed the entire Trek literary universe.
If you were into DS9, there is a whole passel of books there, nearly too numerous to mention.
The "Destiny" trilogy just recently came out in the last six months or so, and fully resolves the Borg issue (people, don't start...). If you follow the list, you will enjoy "Destiny" better, but you can start with "Destiny", then read "A Singular Destiny", "Voyager:Full Circle" and "Titan:Over A Torrent Sea" and be up to date, just six books, but that is the short, short list, and while you'll dig it, you will experience confusion from time to time. For a fuller and more enjoyable Trek literary experience, I'd have to recommend at least the short list, and preferably the long list (if anything else, to improve the authors' royalties as well

).
Hope this helps.