I struggle with high temps too, I feel your pain.
Are you running your lights during the night when temperatures should be cooler, that helps a bit?
I added a height extension to my tent, that helped drop temperature at the canopy a bit too (might not work with CFLs).
The craziest thing I've done to try and control temps is to make an impromptu swamp cooler. I used an old styrofoam cooler and mounted my intake duct on one side, air holes on the top (opposite side), then cycled in cold paks from the freezer. It was hokey as hell and more work than it needed to be but I managed to drop my tent temperatures by 5-10 degrees this way.
I also found that moving from CFLs to LEDs helped a bit. Sounds counter intuitive but CFLs being so close to the canopy really increased the heat right at the canopy. Even though my LEDs create more heat, that heat is vented away from the canopy.
Once I have the funds I'm going to invest in a proper vent fan, vent outside the house, and use a Titan controller to adjust the fan speed to maintain correct temps.