Bosshog Raceway is a favorite of mine.  Turns 1 and 4 are sharp and you have to use some braking and then coast into the corner.  The long sweeping backstretch makes for some fast speeds.  Both the high and low lines work well here, but with the narrow track its hard to carry speed from the inside if a car is on your outside.  Along the back the high line will carry more speed.  Download is on the main page at the bottom.