I tried store-bought seitan a long time ago, when I first went vegetarian, and thought it was awful. I used it in a stir-fry. Mike and I each took one bite and we threw the entire thing out. It wasn't until a while later when I tried seitan at the hot bar at Whole Foods that I realized it could be delicious.
The first time I made it at home, I followed the recipe for Seitan o' Greatness from the Post Punk Kitchen forums. What a difference! Not only was it much, much cheaper, but it was also tasty as well!
I've now made seitan at home a dozen times or more, and I tweak the recipe each time. This is a rough estimation of the way I make it at home, but you may need more or less liquid or dry ingredients. You can add anything you like to this - I often make an Italian-ish version, but go crazy. When you see vegetarian sausages in the refrigerated section, often they're an offshoot of seitan, so if the flavors interest you, try them on your own. Use this in any recipe calling for meat or meat substitutes. I even like to eat it on it's own - it's incredibly filling!
Also, this recipe can be time consuming. Plan ahead, and feel free to make large batches to store in the freezer - it freezes very well.
The version I have a picture of below has sundried tomatoes and fennel seed. I soaked sundried tomatoes in hot water and used that as the liquid, then added Italian seasoning, minced garlic, and fennel seeds. Soon I'd like to try butternut squash, sage, and toasted pecan!
Note: I find vital wheat gluten in the bulk section of my local health food store. Some Whole Foods Markets also carry it, both in bulk and in the flours section. You can also use soy flour instead of chickpea flour, or more vital wheat gluten, but I like the texture that chickpea flour gives the seitan. You can find it easily at an Indian grocery store.
Any additional seasoning that you like - cracked pepper, herbs, curry powder, soy sauce, toasted sesame oil, Italian herbs, sauteed vegetables or fruits, garlic, nuts, etc. Make sure you do add some flavors, as this is a very basic recipe and rather bland on its own.
In the bowl of a stand mixer, mix the flours and attach the dough hook. Add liquid, olive oil, and salt and mix until the dough comes together without sticking to the bottom of the bowl. (This may require adding additional flour or liquid - it's never worked the same twice for me.)
Once the dough comes together, let it knead for 10 minutes. Let rest for 30 minutes, then knead for another 10 minutes.
While the dough is going through it's final kneading time, take a large skillet and place a metal steaming basket inside, along with 1-2 inches of water. Remove the dough, cut into four equal pieces, and shape as desired. Place onto the steaming basket, cover, and steam for 45 minutes, adding additional water as needed. Let cool while still covered, and store for later or use as needed.