I'm doing a winter Eastern Front diorama, and I don't know too much about weathering my troops into that sort of scene. I actually don't know much about weathering at all. I want the wet/muddy/snowy/dirty and cold effect. Any suggestions or tips? Much appreciated.

Here ya go, young man. The March 2012 Model Military Int'l mag has an ad for this outfit:
http://www.hobbyeasy.com/en/category/Paints/PAPIG/maker/MARU.html%22
MIG products is another good place to look for nice pigments that can be mixed. Check some of the model question forums for more tips. The Hyperscale tab at the bottom of the Great Model site has a figures link for question just like yours.
There are many different ways of doing the mud and slush and there are a number of quality products out there that will fit your needs. Good luck.
Ironmike

Hi Conor,
Here is an item that might help you:
http://www.greatmodels.com/~smartcart/cgi/display.cgi?item_num=MIGS226
It is on Great Model web site. A bit expensive but the powers go a long way. I use them on armor to muddy up the tracks and wheels and such. Great for around the legs and feet of figures.
Ironmike

I found a store on ebay that has the same set for $30, but I agree if something like that is what gets the job done, then it's worth every penny. Any suggestions for a good primer? If it's not snowing too bad here tomorrow I'm going to get some more paints. Thanks again

I just airbrush on Tamiya white acrylic. It provides a very good base for acrylics, either brushed or airbrushed.

HTH,

I bought the Tamiya acrylic today and just started on two DML grenadiers. It works great! The paint seemed to dry on right away, only problem being that it eliminated some of the finer details (buttons, belt straps), but that's my own fault. I'll get the hang of it in time. Soon enough I'll have to get an airbrush...
Pictures coming soon