There is a legal (although somewhat time consuming) way around this problem.

If you want to play songs purchased from iTunes on your PSP, you need to burn them to a CD first. Apple allows you to make an audio CD in iTunes by burning tracks from your iTunes library to disk. These can be several songs from the same artist or a playlist of your favorite tracks from many artists. The following steps illustrate how to burn, rip and encode via CD burning.

1. First create a new playlist in iTunes and name it something like "New Audio CD".

2. Add songs to your playlist until you have approximately 72-minutes of music, which is the maximum supported by Audio CDs.

3. Verify your CD burning preferences in iTunes by opening Edit > Preferences > Advanced and checking the button next to Audio CD on the Burning tab.

4. After verifying preferences, click the Burn Disk button.

Converting iTunes to the PSP using Virtual CD-RW drive

NoteBurner installs a virtual CD-RW, it helps you burn any unprotected or DRM protected M4P, M4a, WMA music files onto the virtual CD, rips tracks on the virtual CD, encodes tracks onto MP3, WAV or WMA music files. It can repeat this audio converting procedure until your whole music collection is done.

Since the virtual CD emulates your computer RAM and hard disk as erasable CD-RW drive (Virtual CD-RW), the converting speed is faster than any other m4p to mp3 conversion programs.

listen to iTunes music on Sony PSP:

Now that the Sony PSP has a Web browser along with its existing wireless capabilities, this makes it possible to listen to iTunes music library on PSP, even though the library's actually on Macintosh.

What you need to do is to make sure that your Sony Playstation Portable (PSP) has been updated to the 2.0 firmware release and also make sure that you have a Mac running Mac OS X 10.3 or newer, and you need to download a copy of the application named Dot Tunes.

Dot Tunes looks at your iTunes library and generates a simple web page based on Album or Artist listings that can be accessed across the internet. Once you have generated the web page, it's a simple matter of bookmarking the page in Safari and syncing that bookmark to your web browser on your PSP. You can then access your itunes library with the Dot Tunes web interface and easily navigate to a specific song by artist or album listing. Dot Tunes' simple web based interface is ideal for navigating to a song from the tiny screen of your PSP's web browser. You can then download the song to your Music directory on your PSP.