Hi all, long time lurker, first time poster...
I wanted to tune in on the topic as I had the same problem 2 years ago and became somewhat proficient since in texturing models.
To start off, I usually use 3D Coat for all my texture needs (Also for high-res detail sculpting, but thats beside the point) other than tiling Terrain textures (I use Gimp/PS for that)... its a tool were you can paint your finished model in full 3d. And even paint specular / normals at the same time.
But as this is a commercial product costing a sum (worth it if you ask me), you will be glad to hear that Blender itself has the same capabilities built in since 2.5:
I have never actually used the 3d texture paint mode in Blender, but if its anywhere near as useful as the paint room in 3D Coat, I would choose this tool over Gimp/PS for texturing a model anyday.... nothing speeds up the texturing process more as being able to see the final result (more or less, minus actual lighting and FX of course) in realtime while you paint. IMO, of course.
Hope this helps