I read mostly romance, so I would recommend Lynn Viehl (you do need to read this series in order). Hers are laced with elements of romantic suspense. I would also recommend J.R. Ward (you can pretty much read the first 3 out of order, but after that, you will need to stick to the order in which they come out). Both these series are a bit on the graphic side, though. So if you don't like that, then it will be better to skip. Both involve vampires.
If you like shifters.changelings, Christine Warren's The Others series and Nalini Singh's Changeling/Psy series are quite good. Neither is too graphic.