Hi busold
Welcome to the Vodafone eForum its always good to see new faces
It's really simple to find the information you're looking for all you need to do is place the SIM from your PAYG dongle into a Vodafone handset and type *#100# from the handset.
This will then display your mobile number so you can top up
If there is anything else in the future give us a shout and we'll be in touch.
Thanks
Matthew
eForum Team