just figured this out today... http://www.filefront.com/9637416/DDS-Plugin-for-Photoshop/
No idea if anyone else knows about this..
however this pluggin is for photoshop and it creates .dds files..
but also it has a filter to create tangent space normal maps..
not the grey scale ones... but the purpley blue ones..
install the pluggin then
create your unit textures and texture your uv mapped unit..
open the .dds texture in photoshop then click filters, nvidia tool, normalmapfilter
choose the appropriate settings to create the tangent space normal map.
hope someone finds this usefull