Congratulations Rob :-)
AFAIK new cards are installed with the new 0.9x IDEDOS, so should be OK
for start and then you can update later. Previously the most important
caution was to upgrade from 0.84 to 0.9x before starting to get familiar
with it. So: check your version.
If you want to have the convenience of having tons of stuff on the
device, I advertise my site here:
http://c64.rulez.org/xlfiles/ which
hosts complete FTP archives converted to IDE64 use (e.g. 16 char file
names, all uncompressed from zip, rar, tar.gz, zipcode whatever those
FTP sites use...).
Lion