Okay so I decided against gettin a block of black walnut to make a new riser.  I am instead going to get a pair of riser blocks, out of either superaction, or some type of solid wood.  SO my question is what should I get.  My limbs are black walnut and maple with black glass.  SO I dont know much about wood types, I like gray superaction, but was wondering what you guys thought would go good with those black limbs?

The gray actionwood would look pretty good with the black glass.  You can always use some white or brighter colors as accents.
Not only in walnut, but really any time you use a single block of wood it doesn't hurt to put an "accent" piece into the riser for strength.  For the same reasons cabinet makers will cut a single board and glue it back up, or use multiple boards with glue lines.  The consistency you see in actionwood is for these same reasons.

Here is one I did for my son-in-law It is Binghams  68" longbow, but as you can see the maple, bacote, difficult to see the red phenolic inbetween the bacote stripe, There is brown action wood on both the back and the belly in the handle. The limb laminations were bacote hence the contrast.

I like the grey and black color scheme your looking at it (the bow) should be a looker when your done.

Mike  

I just finished a 3pc TD with blk limbs/gray actionwood riser with a osage accent stripe and it looks awesome I don't know how to do photobucket or I'd post a pic.

Let's see if this works!