Da Gunz By James, pics from GW

40k3 and WFB between them provide a good source for many of the guns an aspiring nob needs. Here are some recommendations.

Six-Shootas Six-Shootas look like Necromundian Stub Guns, or the sort of pistols you see in westerns. Some 40k3 ork models still have them, like the Spanners.
Sluggaz Sluggaz are the basic ork pistol these days. Just look at the plastic ones in the plastic 40k3 Ork Boys box if you need an example. This particular example is from the 40k3 nob.
Shootas Shootas are the basic 40k3 ork 2-handed gun. Good examples are contained on the 40k3 Ork Boys plastic sprue. This one is a Kustom Shoota from an ork nob model.
Kannonz Kannons are ork shotguns. This particularly example is from Necromunda.
Blunderbuss I can't think of a single good blunderbuss model made by GW. I recommend getting a Kannon and turning the end of the barrel into a cone shape.	No Picture Available
Bow Try raiding WFB models, or scratchbuilding one. How hard can it be?	No Picture Available
Crossbow There are several possible crossbow models in the WFB range. Check them out.
'Eavy Shoota Most vehicles come with a varient of a 'eavy shoota already mounted. For any others, I recommend Forgeworld's Twin Big Shootas.
Spear Guns Unless you can find the original GM model (shown here), it looks like the bits box is calling. Plastic WFB spears are clearly a Gork-send!
Rokkit Launcher Forgeworld do a very nice Rokkit Launcher suitable for GM use. Alternatively, you may be able to find an original GM rokkit launcher.
Scorcha Forgeworld produce nice scorchas, although GW also makes a nice trak-mounted scorcha model.
Harpoon Guns Check out WFB bolt throwers and spear chukkas to give you inspiration for Harpoon Guns. Hey, you may even be lucky enough to get an original GM Harpoon Gun if you look carefully.
Stikkbombz Stikkbombz are sticks with bombs on the end. Check out the 40k3 Ork Stikkbomberz box set for plenty of lovely stikkbombz.