yeah, check out noiseninja or neatimage 

I think both have free/ trial versions.  They are a little time consuming for the trial versions but good for testing things out and seeing if it works.

If an image has LOTS of noise, nothing is going to get it good enough for stock, but the programs are very helpful if there is only a bit of noise.  In the future make sure you only shoot on ISO 100.  For point and shoot cameras like the S5 this is particularly important.

I also have Neat Image, but using proper lighting, DSLR and prime lens reduces the needs of using it.  Make sure you only apply the minimal level of noise reduction on the area that really needs it and sharpen the area a bit afterward as some details would be lost during the noise reduction process.

I agree with michealo

I agree resizing is the best way but I also in photoshop sometimes adjust the color, if I can darken something if it is green/black etc.. and it helps.
Sometimes I have used filters to soften the image (example of a sky) but then erased parts so it still appears sharp).

Hey There,

 The best way besides good glass and a descent sensor is to over expose your image. Just like in the old days of neg. film. Expose for the shadows and develop for the highlights. You need to shoot in Raw to really be able to control the develop part of the system. Keep those Histograms up high everyone.

Best,
AVAVA

I use Imagenomic Noiseware. It's not free but it's excellent and it's very flexible.

I also use Noiseware and find it does the job well.