To add on to Mylenium's response:

After you rasterize your desired font then go to the Layers panel and click the "lock transparent pixels" icon on the layer. Using many of Photoshop's brush presets such as Air brush, dry brush etc, you can create the textures that you are looking for. This way you can also create some color variations in addition to the washed out look.

-Sharon

The mottled affect can be done by filling a layer mask with Filter > Render Clouds.  use a Levels command directly to the layer mask to fine tune.

The blotchy type can be done by rasterizing the type layer, and adding noise, then gausian blur.

The font looks like Arial.

Do you need the texture on the background?  It looks like artefacts from upsizing, so probably not, but too clean a background would look too fake IMO.

If you have a nicely textured background layer(s) which you are putting the text on, one of the most "natural" looking ways to achieve what you want is to use the "blend if" in the blending options of the Layer Style Effects dialog. It is actually pretty darn amazing what can be achieved. Sadly, there is no formula: it depends on what you are using but if you play with it a bit you may well end up quite happy. I do a lot of "art journalling" in Photoshop and getting distressed looking text is one of my most frequent tasks. All of the suggestions so far are excellent but even if you use any of them, still try "blend if" as a finishing touch. If you were trying to make this look like text on fabric or brick I might suggest displacement maps, too, as an alternative means of achieving textural reality, so to speak.

Sorry if I am off base Trevor, I am afraid I am pretty much self taught and some of the things that don't seem to sink in are things like tonal values, calibration, and the like no matter how hard I try to stuff them in. I confess I am a button pusher and just play until something works regardless of what it is supposed to be for. Thank goodness for the millions of tutorials on the web and for a lot of really decent manuals out there. So, I probably shouldn't have mixed in. I do use layer blend modes (just about every layer) and agree that they are power houses but for me, the "blend if" seems to work best for emulating writing on crumpled paper or cardboard or paint smeared bases. Text that is distressed because it is part and parcel of an object which is itself distressed. Until I discovered blend if I used to try to use displacement maps but compared to blend if layer styles, a displacement map is a heck of a lot of work to produce and tweak.  I am modifying the underlaying layer (if that makes sense) using the bottom most slider, not the text layer so that the text is blending depending upon what it is placed upon. I guess that means I am not mucking around with the tonal value of the text per se but rather the tonal value of the layer that the text is on is modifying the text. Why do I have the feeling I am digging myself a deeper hole? Sigh. Anyway, the finished project posted is absolutely exactly what I would have used blend if to achieve. Would not look quite the same because mine would have major distressing along the vertical folds on the lettering. And now I have to go try messing with the letter aligning trick-- sounds cool and if that is what the poster used, looks wonderful. So far, all I have done with that is transformed individual letters with warp which is mega stylized and this looks more like an old misaligned typewriter.