Fastfwd01, you haven't told us either how long your stem is or what angle, just the cms of spacers under it. If you are looking for handlebars lower relative to your seat you can do several things and all are easy.
First, take of the stem and spacers and replace with the spacers on top of the stem. (This will quickly tell you if you even want your bars lower and is easy to undo.) Second, look at stems with a lower angle of rise. -17 degrees is the equivalent to the old fashioned horizontal stem. You can take a stem that has a positive rise of more than 17 degrees and turn it upside down to go lower than a horizontal stem.
And last: if you are concerned about real fit more than "x" cms of bar drop to be properly hip - one way to get the effect of more bar drop is to go to a longer stem. For me, I can place the handlebars anywhere on an imaginary line that slopes up 1 cm of stem spacer by 2 cm of horizontal "reach" with no change in either my shoulder location or arm bend and within reason, no change in comfort.