newbie file/DB processing

[len]

I am in the process of learning python.  I have bought Learning Python
by Mark Lutz, printed a copy of Dive into Python and various other
books and looked at several tutorials.  I have started a stupid little
project in python and things are proceeding well.  I am an old time
cobol programmer from the IBM 360/370 eria and this ingrained idea of
file processing using file definition (FD's) I believe  is causing me
problems because I think python requires a different way of looking at
datafiles and I haven't really gotten my brain around it yet.  I would
like to create a small sequential file, processing at first to store a
group id, name, amount, and date which I can add to delete from and
update. Could someone point me to some code that would show me how this
is done in python.  Eventually, I intend to expand my little program to
process this file as a flat comma delimited file, move it to some type
of indexed file and finally to some RDBMS system.  My little program
started out at about 9 lines of code and is now at about 100 with 5 or
six functions which I will eventually change to classes (I need to
learn OOP to but one step at a time).

So any recommendations of code, online tutorial, or book that might
address this file processing/database would be appreciated

Thanks 
Len