Exporting audio files hogging up storage space

I've been exporting several wave files from iReal to my computer with great success. Each time I get the files onto my hard drive through "filesharing" in iTunes, I delete them from iTunes, thinking that this will keep my storage space freed up on my phone. It appears, though, that something is being stored somewhere because all of my storage space in my phone has been hogged up in the process. I only have a handful of playlists stored in my iReal, totaling 1,500 songs and yet it shows 7.5 gigs of documents and data taking up space on my phone. Does this sound right? As I mentioned, I'm deleting them from iTunes each time I transfer them to my computer. Are there hidden files somewhere that I need to get rid of? Does 1,500 songs taking up 7.5 gigs of space sound right?

I can't address the .wav issues, but just for comparison: The total space used on my iPod by iRealb is 49.1 Mb. I have about 900 song files and the "UserSongs.plist" takes up less than 500 kb.

1500 songs should only be a few MB.
You can look in your iPhone Settings -> General -> Usage and see where the memory is going in relation to each app
What does it say for iReal b?

7.5 gigs for IReal B. That's where I got that number from. It's back to normal now. 100 megs. I wound up finding out that I had to do more than delete the wav files from ITunes after I've brought them over to my hard drive. I was told that I actually have to sinc to ITunes to get rid of them from the phone. What I wound up doing, instead, was uninstalling and reinstalling the app and this returned my storage space back normal. Now here's a new question: Do I have to purchase my styles packs again? They didn't show up in my reinstall. I may have to start another thread on this.