The old Romans liked them. Piedmont was famous for them in Renaissance times. Today Italy, not France, is the largest producer, and every variety of truffle is found here. Most come into the markets in the late fall and winter.
Tartufi bianchi: Tuber magnatum pico, the most prized, come from around Alba and Asti in Piedmont. They've become a silly international status item, with prices up to $100,000 a kilo. There are other small areas through Italy, as far as the Molise and Basilicata.
Similar, but not quite as fragrant as the tartufi bianchi are the borchi and bagnoli white truffles (also called 'bianchetti' or tartufo marzolo or marzaiuolo). These are found around Tuscany and Umbria, especially near San Miniato, also around Aqualagna, south of Urbino in the Marche, and around San Pietro Avellana, north of Isernia in the Molise. The borchi appear in the late winter.
Tartufi neri: the black ones are the pride of Umbria, though they're found in Lombardy, all through central Italy and as far south as Calabria. The same as the black truffles of Perigord. Many think they're just as tasty as the rarer bianchi. There's a similar species in the same regions called the tartufo nero invernale—not as good.
Tartufi estivi neri, or scorzone: 'summer truffles' are black outside, white within. More common and not nearly as intense. Found in the other truffle zones.
Tartufi uncinati: like scorzone, only appearing in the autumn, in chilly northern valleys.
Tartufi nero liscio: 'smooth black', found in the white truffle zones.
Tartufi della sabbia: 'sand truffles'; see tuvara.
Italians are more creative with their truffles than the French. They grate them on pasta and risottos, infuse them in oil, add them to salads, meat and seafood dishes, to antipasti with bresaola or carpaccio, or slip them under the skin of roast fowl.
Fiere del Tartufo:
Alba: Fiera Internazionale del Tartufo Bianco di Alba, October through mid-November. The big show; like a film festival.
Murisengo (Piedmont): mid-October.
Moncalvo (Piedmont): late October.
Savigno (near Bologna): early November.
San Miniato: last three weekends of November (also in Tuscany, Balconevisi and Corazzano have fairs in October, San Giovanni d'Asso has one in November, La Serra in September).
Acqualagna (Marche): Fiera Nazionale el Tartufo Bianco: late October-November.
Norcia (Umbria): mid-February.
Campoli (Abruzzo): late November
Colliano (Campania): early October.
Isernia (Molise): early December.
San Pietro Avellana (Molise): mid-August.