Hi,
I just thought I'd add something to this old thread. It seems some people have been having trouble getting the code to work. I too had my fair share of problems and have posted them below in an effort to help others in the future who may have similar problems. I'm not sure if the problems of the previous 2 poster are related to mine, but perhaps they have found a solution at this stage.
Anyway, I bought the SCP1000 breakout board from sparkfun and tried to interface it to an arduino duemilnova. The first problem was the 5V I/O pins on the arduino and the 3.3V pins on the SCP1000. To overcome this I got the logic level converters also from sparkfun and wired them up. Still the code did not work. The details provided by sparkfun for the logic level converters are a little misleading if not read carefully, on the low voltage side you will get half of the voltage on the high side, and not the actual low voltage. The problem I had was that I was driving 2.5V to the SCP1000 I/O pins and had the SCP1000 powered of a 3.3V supply. There is mention in the datasheet for the SCP1000 that Vcc cannot differ from the I/O voltages by more than a certain amount. (I don't have to hand the exact values). So the solution was to power the SCP1000 of 2.5V. This actually produces less error comapared to a higher voltage according to the datasheet also, which is a bonus. I have been getting what seem to be acuarate readings of pressure and temperature ever since.
Anyway hopfully this post will save somebody some time in getting their sensor to work.