Like Philamac said, it depends on what you want to do with it. If you need a mug to lather in, or if you need a soap mug, or if you want one mug to do both? A cheap coffee cup can work in a pinch, and some members prefer using a large cappuccino cup or rice bowl to work lather in. Welcome and good luck! I suggest checking out your local department/housewares stores, or even thrift stores if you're not picky. If you want something nicer or more individual, keep an eye online and here on the B/S/T. Welcome!
If I were you, I'd take my time before buying a mug. There are lots of high end ones available, but you might find that you really don't need it once you've been shaving for a while. I've found that all I use is a regular spare mug from my kitchen to hold my puck of Williams. I keep all of my other soaps in bowls. The mug for the Williams is just a temporary thing--it take up too much space on my counter and I'll probably move it to something smaller when I find something cool.
If you want it for lather, I'd agree with the cappuccino/latte cup from somewhere like Target. Plenty big, and it gives you a handle to hold onto. Plus, it's cheap. If you decide you don't like it or you're going to just face lather, not much capital tied up. Another option might be a stainless steel dog bowl. Various sizes and you can plop it into the hot water in the sink to keep the lather warm if you are so inclined.
Keeping your mug cheap and simple gives you lots of leeway later on. Once you decide what you like and don't like, you can adjust. Maybe buy a scuttle or a decorative mug. Maybe scrap the whole thing. Spend that money on soap or cologne or a new razor.
IMHO, not much call for a special mug, I seem to do just fine with a latte mug it's large, not too deep and only set me back a couple bucks. Although I must confess I haven't used it much for lathering lately as I've taken more and more to face lathering.
I agree a decent coffee/latte mug will work fine you can see the mug I use in the shave den thread in the darkroom only bad thing about mine is since it's a thin plastic it looses heat rather quickly but since my bathroom has two sinks I just dump an electric kettle of boiling water into the other sink to keep it nice and warm.
1) Go into kitchen.
2) Take out a cereal bowl.
3) Take out Cheerios (or similar).
4) Pretend like you're pouring cereal into the bowl (it's really going into your pocket)
5) Tell your mom you're just going to watch T.V. while you eat your cereal.
6) Exit kitchen.
7) Quickly deposit said bowl into your secret shave den.
* (Not sure what to do about the Cheerios in your pocket...)
Stainless steel - 2 bowls - 1 lg, 1 small. (For those of us who don't have two sinks in the john!)
Fill big bowl half way with super hot water and float second bowl in it. Lather away. Worx great, warm lather, lots of room, a sort of floating scuttle/lather bowl. Yeah! (With the set up on the counter by the sink you can still run water for cleaning your razor bw passes.)
The SS bowls IMHO are much better than ceramic. They heat up very easily and work great. Ceramic tends to leave your lather cold - yech! And, I find the standard scuttles are too small for making lather, they are really just to keep your brush warm. Warm brush, cold lather - huh?
And the comment about the dog bowl - not a bad idea actually! I have seen some pretty good quality stainless bowls for pooches that would work great for doing the floating lather bowl idea. Just don't tell! If anybody asks, just say they are a high quality nickel plated shaving set!!
When i first started I used a random coffee mug from the kitchen. I then got a lecture from my girlfriend on why we dont use kitchen mugs in the bathroom. I dont remember it all, but it involved something about colors and decoration.
However, it did end on a good point because she has become determined to find me the perfect shave mug. So far we have gone through several options, either because I didnt like them so much, or because she decided it was important for soemthing else. My only requirements were that it do the job well, and retain heat because I do enjoy a hot lather.
So far we have gone through...
1. Self Watering planter - I saw this mentioned on here somewhere and so she picked one up from walmart. It worked out pretty well actually, though it looked a little odd on the cabinet. It had a rough texture to the inside but I dont know if its good or bad. Might help lathering, might induce shedding of the brush. Was 6 bucks at walmart and did just fine till it ended up with a plant in it.
2. Soup Mug - Target had this for 5 bucks and it worked just fine. It holds the puck of soap for La'Occotain perfectly and retains heat pretty well. Unfortunatly she didnt know I kept the soap in it and tried to use it when she brushed her teeth. Not a plesant morning. Make sure you inform your SO that mugs may be booby trapped.
3. Ramikin - Apparently they are for making souflles or something. I used them to hold dip. You can find them at most any store with a decent baking section in a variety of sizes. They hold heat well and do fine. 6 bucks.
4. Capachino mug - Worked fine, but the one I got didnt keep the heat so well for some reason but for less than 5 bucks it does fine. It will probably end up home to a soap soon.
5. My favorite so far is an old fasioned mortar and pestle for grinding up herbs and medicine. She found one out of a nice dark stone that is just the right size and holds heat like you would not believe. Well, you probably would since its stone. Anyways, its more of a stone bowl than anything, but thicker since your supposed to grind things in it. It has a nice solid bottom so it doesnt rock or tip, and the inside is smooth and round. It is perfect for creams and was less than 20 bucks. Its my favorite till she steals it for something or finds something better.