For Ripping/Converting MP3s and WMAs, I used Music Match that came with the Player. If you goto File/Convert you can explore to the directory the MP3s are at, choose MP3 on the left, choose WMA on the right, select the MP3s you wanna convert then start it. Takes about 30 seconds AVG per Mp3 to Wma. Firstly my MP3s are at 128, the WMA comes out 96 when converted. And they are a bit smaller, but any 96 file would be smaller than 128. The only problem is you have to use the latest Microsoft Media 7 to copy the WMAs to the Nomad, BUT you can use it to copy MP3's.
Also remember after you flash to the latest firmware for the Nomad you need to format the flash card to get the new format, ability to Use WMA and LongFileNames. THE ONLY problem I have with WMA is that the Nomad II lists everything as (name).WMA. I believe its in the ID tag created by Music Match but I haven't bothered with fighting it yet.
Anyone else have any suggestions, or comments go ahead. I love the Nomad II just to play with, but the Computer still does 99% of my MP3 playing at home.