Although there are many variations of Tiramisù, the original recipe (that was born in Veneto quite recently, at the beginning of Twentieth century) is made with raw and not cooked eggs.
Personally, I think there is no use in scaring people (apart from "at risk" subjects) about raw eggs if they're absolutely fresh, the provenience is well known and you don't contaminate the inside with the shell... and, in any case, the "raw" recipe is very quick and easy and you don't need much experience to get the best results!
The procedure of the "classic" recipe is just the one quoted by Svadhistana. As for the doses, as W. DeBord said there are no rules apart from your taste! These are the easiest:
Each person,
1 Egg
3 1/2 oz Mascarpone
1 tbsp (full) sugar
Beat the egg yolks with the sugar until they're "writing", mix with the Mascarpone, then incorporate very gently the whisked whites. I don't add anything more to the cream, but some vanilla flavour added to the egg yolks can be a good idea; I'm a little more doubtful about chocolate. Soak the cookies with coffee and liqueur, make a layer of cookies, one of cream, another of cookies, then cover with the reamining cream and sprinkle with cocoa powder or chocolate. Keep refrigerated for at least 3-4 hours.
Coffee: there are no defined doses as you just need the amount required to wet the cookies without breaking them, and also the type of coffee depends on your taste...I use expresso, or coffee made with the "Moka" coffee-maker (as you may know, it's very popular here in Italy) but any coffee can be good if you like it! I usually flavour it with a coffee liqueur like Kahlua or Tia Maria, but also with Rum or an orange liqueur (Cointreau or Grand Marnier).
Cookies: suppose that your "lady fingers" are our "Savoiardi"...personally, I never make them at home as, apart from the time I spare, the commercial ones are MUCH better! (At least, much better than anything I could do...

). I have always found very easily the Italian Savoiardi abroad and suppose they're available everywhere in US. Can't say how many Savoiardi you need as I never count them...but a package serves about 6. Don't soak them too much (the center must remain dry) as they'll become softer as you're keeping your Tiramisù aside before serving. If the cookies are too wet from the beginning, the Tiramisù will end up watery.
Chocolate: I usually sprinkle the surface with bitter cocoa powder (and never put chocolate inside). Since the Tiramisù is supposed to be kept aside at least 3-4 hours, it becomes quite wet and it's unlikely people choke on it. Anyway, finely ground chocolate (or thin chocolate leaves) can surely make the recipe very yummy!
Mascarpone: I'm doubtful about homemade mascarpone...and, all considered, although it's more expensive than in Italy I don't think it's SO expensive you must make your own! Here in Italy, fresh mascarpone is available, and it's obviously much better than the packed commercial brands. When I was forced to use packed mascarpone (in example, out of Italy) I found out that with some brands I had major problems to amalgamate the eggs with it as they remain separated (don't know the English word... I mean the same thing it happens when you fail making mayo). So, my advice is to try making Tiramisù in advance and then to use always the same Mascarpone brand you already know it's good to avoid bad surprises...
Pongi