I'll take a stab at this. If you're getting a gyuto, you're getting a Japanese made knife, so I'm not sure where your question comes in about German vs. Japanese. Still, for starters: most gyutos are made with a "French" profile; most German knives have a "German" profile. The former has less belly -- or a less dramatic curve up to the tip, or are "flatter" (not flat). Take your pick of which of those three distinctions are clearest to you, because I'm trying to say the same thing three different ways. Look for our very own Boar D. Laze's post making all this clearer and more accurate, here: http://www.cheftalk.com/forum/thread/62065/french-and-german-chef-s-knives-profiles-in-cutting . Generally German knives will have guaranteed wonderful fit and finish and will be heavier (which some people like, most don't if they spend time using the knife and not just holding it for a moment when making a purchasing decision).
Generally German steels are softer, too. They won't take as steep an edge (which means less sharp), they're thicker, which means they wont' "feel" as sharp, but they are very robust. They respond well to steeling, as soft steel may usually do. (Gross generalization maybe). They won't keep an edge as well as a Japanese knife.
Carbon knives will be easier to sharpen, and therefore sharper. In general. On the other hand, they take more care (must be toweled dry frequently in order to prevent rust, and must have any rust attended to quickly). They may impart some flavor to food, which is a bad thing and may impart some color, too; they develop a patina which mitigates this almost 100% after a while, but that may need to be re-built after sharpening or scrubbing. Cheaper carbon knives will smell bad when coming up against lemons or onions or sweet potatoes, too.
Also, there are very low stain carbons which won't have these problems. And these "problems" are really not bad at all if you attend to your knife. Takes more immediate care and feeding.
Stainless takes similar care, but is not so demanding as to when you do it. Like, it's ok to leave the knife wet for 10 minutes. Carbon in general feels better on the stone when you sharpen freehand (goes along with "easier to sharpen").
Do you need recommendations for the "usual suspects" as to knives to consider? There are lots of questions to ask about carbon vs stainless, about whether you have a preference in handles (western = "yo" or Japanese = "wa" handles), about how important stiffness vs flexibility is to you, about particular kinds of handles within your preference for wa- vs yo-. There are also several threads that give this sort of advice once you decide which preference you have and or figure out that some things don't matter to you. (I didn't even get into preference in terms of appearance -- damascus, kurochi... that sort of thing).
Do you have a good cutting board? Some of the lesser ones will dull a knife very quickly (don't ever use a glass cutting board! For some reason that's not 100% obvious to everyone. End-grain hardwoods will be nicer to your edge than Edge-grain or synthetic materials or something so obviously bad as granite or glass).
My first stone was a combo-stone in 1000 and 4000 from JCK, and I still think it's a good first stone. If not buying a combo stone, it depends... but you want something between 1000 and 2000 grit in a waterstone. I've used a 2000 that cut faster than my 1000... often you'll hear a recommendation for the 12000 Bester. At its price point its probably a great choice (probably better than my JCK 1000, not as good as the Gesshin 2000...) For $100 you can get a very good 1000 or 1200 grit stone. You could spend less and the remainder toward a Suehiro stone holder.
As my sharpening-teacher said, though, it ends up being more about your ability to hold an angle than about the stone itself. There are differences... but there are bigger differences that matter more early on in skill levels.
Get a stone holder with a tray, too; or a "sink bridge" or something to help you keep a neat work space with water stones. Particularly if it's a small work space, this matters a lot.
I'll throw out some brand names -- in stainless, look at the Mac gyuto, the Masamoto VG (better profile, less stiff, more expensive than the Mac). And look at the Fujiwara FKM -- which I've never used, but seems to be a strong recommendation as an entry J-knife these days.
The JCK CarboNext -- a low-stain carbon. It won't be sharpened well, even if you pay for the "extra sharp" fee. Or mine wasn't. But it's a very thin bladed western handled knife (not "laser" thin, mind you, but it'll easily get sharper than any German knife you may have experienced). It's not stainless, but it's very forgiving of a carbon and won't impart a flavor to foods. Actually mine has an overgrind issue, so not altogether happy with the "fit" (or is it "finish"?). Actually the finish in other regards is good.
Carbon - you could go with a French knife, a Sabatier (Thiers-Issard, or K-Sabatier) -- there are thinner Japanese knives, but these are not thick by any means, they have the profile that defines "French profile" if that's what you want, they're inexpensive relative to anything else this good.
It only gets 1000x more complicated from there. But I don't want to keep shooting in the dark about what your preferences might be....
My own first good knives were the Sab carbons; I also have a couple of German knives -- one of which is my big hacker, a Wusthof Classic 10" chef's); I got the CarboNext as a first J-knife, which at its price point is still a good recommendation, though the overgrind makes me a bit wary; I also got a Yoshihiro stainless, as a first wa- handled knife, and once sharpened it's been a joy to use. I don't have a budget for some of the still more highly recommended knives you may run into.... but I share my trajectory thus far in order to partly make recommendations (with way too little info to do that responsibly) but mostly just to show where my own prejudices have led me.
Anyway... tell us more what you want. I'm sure others will be around to ask still more specific/better questions, to help you think through your purchasing decisions.
Edited by Wagstaff - 8/13/11 at 6:34am