OK, so I checked and I had installed the nvidia drivers as you described (including the cuda toolkit location).  As such, I tried this:
CFLAGS=-I/usr/local/cuda/include LDFLAGS=-L/usr/lib64/nvidia ./configure --program-suffix=\-nvidia

For the record, I uninstalled my previous build first, the -nvidia was just in case I ended up finding it only working for nvidia and wanted to try to run an nvidia one and an ATI one side by side.  When I tried to run cgminer-nvidia, I still get this:
[2011-07-21 09:26:33] Error: Getting Device IDs (num)

I then proceeded to uninstall again, remove the jansson-devel libraries just in case, configure without the program suffix just in case, compile and install again, see the same error when running cgminer, so I edited /etc/ld.so.conf.d/local.conf to remove these two lines:
/opt/ati-stream-sdk-v2.1-lnx64/lib/x86_64/
/opt/ati-stream-sdk-v2.1-lnx64/lib/x86/

I then ran ldoconfig.  I still had to use CFLAGS=-I/usr/local/cuda/include LDFLAGS=-L/usr/lib64/nvidia in order to have gpu mining support enabled even though /etc/ld.so.conf.d/local.conf still had these lines:
/usr/local/cuda/lib64/
/usr/local/cuda/lib/

After all that (some of it perhaps grasping at straws), I STILL get the same error.  Any other thoughts?