Dear Simone,
I'm not 100% what observational record keeping is, and the format you are capturing you observations in, and then how you plan to archive and analysis them ... however, if its something that will allow you to capture an audio recording, and then link text markers to this all using a PDA, and finally transferring it all back to a PC for some serious analysis. In other words a dictation and transcription system on a PDA (pocket pc or palm) then the following might be worth a look;
Audacity for PDAs -
http://www.audiost.com/products.htmI've made a few initial observations from just looking around the web site -
http://www.mobile-learning.blog-city.com/dictation_and_transcription_system__audacity_on_pdas.htm - I've a few reservations. However, if you evaluate it then please tell the world ... it will save me the time. I might get round to using this in March/April when I've got a few focus groups to run

Finally, where did I find out about the software ... well all the credit goes to Andy Black - thanks :-)