Luckily I got access to Audition through the university I work for, ended up using it on a whim earlier this year, and it has become extremely valuable to me. I enjoy sampling, and found Audition very intuitive for me to use, so much so that I think my sampling and audio editing work has shot up.
Adove Audition is one of the best audio editing software out there. It offers a lot of options with it's outstanding comprehensive toolset (such as waveform, spectral display and multitrack). It's great for professional use to both record and edit audio. You can use it to work side by side with other Adobe software (such as After Effects and Premiere). If you're new to audio editing in general, you might need some time to get used to it.
The only downside is that compared to the previous versions of Adobe Audition, this one requires a lot more out of your PC but doesn't offer a whole lot more than the previous versions. So if you have a lower end PC, I would recommend going with one of the older versions such as CS3, CS4 or CS5.
I used to use this program to do ALL of my vocal mixing and it does a great job, but it really doesn't teach you how to REALLY mix and master. You can make shit sound great in this but it doesn't really use the same mixing process that industry standards like Ableton and Logic Pro X use.
This software doesn't come with any built-in sounds, so you can't use it without another instrument. However, the EQ settings here are good, and it is easy to use. You can easily convert songs into different formats, from 64-bit, 192 kHz WAV files to 128kbps MP3 files.