For the tracking room you should use frequency absorption panels (as many as you can afford). The thicker the panel, the lower the frequency removed. Its good to get atleast 4" thick foam for the bass traps (or some thick theatre curtains), and 2" foam for absorbing the mid-high frequencies. Placement is the most important element to treating a room, and hopefully you have atleast some form of carpet -the floor and ceiling are usually the MOST reflective surfaces, and you should choose a room with atleast some form of texture (knockdown, orange peel, anything but flat). However, for a control room, you should have about 70% coverage. And using diffusion panels above and behind your listening position will really help your mixing environment. Again, bass trapping the corners of your walls are essential, and covering up you windows with a thick curtain is necessary too. You don't want to make the room sound completely dead, because that is a unrealistic setting that nobody will ever listen to your music in. Just experiment until there are no standing waves, and very little reflection. If you spend less than $500 per room and are successful, then you did well.