I'm working on creating some posters and I was wondering if there's a good way to give the whole poster a distressed/aged/weathered look to it. Would anyone have some tips or tricks to doing something like that? Thanks so much!

Here's some examples of the kind of look I'd like to aim for:

http://davegamache.com/public/img/articles/poster-zelda.jpg

http://dapperngent.files.wordpress.com/2012/11/star-wars-trilogy-minimalist-posters2.jpg

Hi.

Those use raster images of paper textures without repeating. There are tons of such textures on the net, stock and free ones too.
The only difficulty to manage is the size and the resolution.
You cannot have (non-repeating?) raster textures in a large format with a resolution for a clear print.
If you want the posters to appear only on screen, you can make much smaller ones -and maybe gimp could give you more possibilities with compositing.

If you want to make a high-resolution print than you may experiment with inkscape's filtering effects and print straight from svg.
I can be wrong with that, never really tried to use it.

I attached a svg file with a special version of filter I used for my scratched paint texture




Don't know how it'll render at print anyway.

PS:Apologies to original author (and SW fans) for this lame ripp-off. It was just a quick'n dirty POC.

That filter looks great!