I've been chasing down some of the old books from what I've seen being referred to as the 80's novel continuity. There's a topic further down in this section, where some of these books are linked together by a network of very loose continuity sharing, so that's been a fun chase.
A month or so ago I found decent copies of The Vulcan Academy Murders, which I've surprised myself for neglecting, given that it it looks in on the planet Vulcan and Spock's family, at least according to the back cover discription. About two weeks ago I got a hold of Shadow Lord (hoping there will be some good Sword and Planet action like in Friday's Child), a really nice copy of The Final Reflection, and Uhura's Song (which I've dismissed for the longest time, but I've notice that it's very highly rated in some places, and again for curiosities sake to see how in joins in with the other 80' continuity books).
Less connected to the whole 80's continuity thing, I found a pristine hardcover copy of Reeve-Steven's novel, Federation, at a library sale for only $2.00 yesterday.