In reply to John Burns: Can't really advise on Photoshop - I use Lightroom for most of my stuff so PS just confuses me, but you'll definitely have the tools in there to do it. There'll be plenty of PS users on here who'll know, I'm sure. Dropping out the saturation definitely isn't the way though. Have a hunt around for a button to do a black and white conversion to the image instead - should make the images much stronger straight away. I'm sure your camera will have a black and white option - if you're shooting in Jpeg then that's worth doing. If you shoot in RAW then might as well do it afterwards - don't know what camera you're using but I'd be pretty sure even the most basic point-and-shoot will still have it as a setting. On the filter front, there is probably a function available to you to apply different effects which should feature various filters, so if you find it slap some different ones onto the photo and see what happens - go with what you like (yellow, orange, green... will all do different things depending on the colours and subject matter in the photo). Actually using a real filter on the camera tends to be rarer these days, but it's still out there.
A quick google for something like 'convert colour to black and white photoshop' will give you loads to play around with, and you'll be amazed what you can acheive very quickly. It's worth considering what the shot will look like in black and white when you're taking it as well though.