Does your hall have a sound system? If so, you should be able to take a feed out of it into a laptop. Then get some software (Audacity is an example) that can capture your audio track. Once you have that captured, you can burn CDs, or save as an MP3 etc. This gives you a file that can be downloaded from a suitable website (hopefully your church has it's own site...if not, get one set up...check out carnmoney.org as our own example!)
Hope this helps!