I’m sure this is basic, but I’m in a hurry. How can I rename a bunch of files say, from London 2008 01 to london_2008_01? The 01 is consecutive number, so there would be 02, 03 etc.
tia
Automator? I’m not at my mac, but I think that you can rename files through Automator… whether you can make it take wildcards and do sequential serial numbers, I’m not sure. Failing that, there’s probably some unixy regular-expression magic you can do at the Terminal prompt.
Thanks. 
I got it to work (loading a bunch of pics to a digital frame for my mom) without renaming.
Too late, but if you had felt like spending some money:
A Better Finder Rename
Probably only worth it if you had to do this sort of thing frequently…
open a terminal window.
change the current directory to the one containing the files (in the following, “>” represents the terminal promp, you should not type it). You can get the directory name in your terminal by dragging and dropping the directory/folder into the terminal window.
> cd “path to the directory”
Type this code, which will change all spaces to underscores for all filenames starting with “London”
> perl -e ‘for (@ARGV) { (new = ) =~ s/ //g; rename $_,$new }’ London*
Or Scripts Menu -> Finder Scripts -> Replace Text in Item Names.
You may need to launch Applications/AppleScript/AppleScript Utility & check the “Show Script menu in menu bar” box. AppleScript is incredibly useful.
Adobe Bridge (which comes with a bunch of Adobe products) can also do this trick; I think it’s meant for media files, but it works on anything. I’m not suggesting buying bridge for that function, but you might have it lying around.
Adobe Photoshop, if you happen to have it, can do a batch rename.
I personally use the application “R-name” but I think there’s some small fee for download.