molarman,
Pretty much any tracks that you buy from a legitimate site are WMAs that have the DRM protection, with the exception of iTunes. They have AAC songs that have DRM protection, but they will play on your iPod without any conversion or burning-and-reripping. Of course, iPod will play regular mp3s too. RealPlayer also sells AAC songs, but I'm not sure if they work on the iPod.
Napster has 2 options: pay 9.99 a month and get play-only capability with all songs in their catalog, or don't pay a monthly fee, and you can permanently download songs for 0.99 per track or 9.99 per album. If you pay for the songs that way, you can burn them to CD or transfer to a portable player (although not the iPod; the songs are in WMA).
I did read on the internet somewhere that Apple is supposed to start supporting WMA because of the recent deal with HP. I still find it hard to believe, but I really hope it's true.
crow
EDIT:Here is the blurb that I saw:
Exclusive: HP Working to Get WMA on iPod
HP's blockbuster deal with Apple will have one exciting side effect, I discovered today. The company will be working with Apple to add support for Microsoft's superior Windows Media Audio (WMA) format to the iPod by mid-year. You heard it here first.
Here is the link (that blurb is about 25% of the way down the page):
http://www.winsupersite.com/reviews/ces04.asp