Since you're using SQL 2000 you could potentially use a combination of xp_dirtree and xp_getfiledetails to automate this. Here's a basic template for what you'd need to do.
It's dependant on several things but it's possible. Hope this helps.
--create a temp table called #files with 3 columns
--insert contents of backup directory into table
insert into #files exec exec xp_dirtree 'c:\sqlbackup\log\', 1, 1
--delete rows from table that aren't files
delete #files where [file] <> 1
--now cursor through the rows in #files and for each file, use master.dbo.xp_getfiledetails 'file name' to find out when the file was created.
--if you store the timestamp in the filename then you won't need to use xp_getfiledetails