because you have fl studio 7. there is a editing vst installed in the effects menu. It is called EDISON. What is cool about this plugin is that you can drag and drop ur finished .wav right on to the sequencer. Although if u want to get a chipmunk effect then u want to do the sampling in cool edit pro(you really should download the newest version of cool edit called ADOBE AUDITION 2.0 there are a couple posts of this in the other downloads section). These ways of sampling should do u just fine. Edison is also perfect for the screwed effect. But there is also a whole lot more to do and take into consideration when you're sampling. These tutorials here should help a lot.
YouTube - Warbeats Tutorial - EZ Sampling Part 1 YouTube - Warbeats Tutorial - EZ Sampled Beat Part 2 YouTube - Simple sampling with Edison (FL Studio 7)