By the time you read this, the wine harvests in the northern hemisphere will be well underway. At the time of writing, the reports I've read suggest that no nasty surprises lie in store. But it's not the current vintage that buyers have to be thinking about: these wines are many months away from their rendezvous with the bottling line. If you're thinking about what to buy in the run-up to (dare I mention the word?) Christmas, or even for Midsummer Eve 2005, you should more often be thinking about the years 2002 and 2003.

By the time you read this, the wine harvests in the northern hemisphere will be well underway. At the time of writing, the reports I've read suggest that no nasty surprises lie in store. But it's not the current vintage that buyers have to be thinking about: these wines are many months away from their rendezvous with the bottling line. If you're thinking about what to buy in the run-up to (dare I mention the word?) Christmas, or even for Midsummer Eve 2005, you should more often be thinking about the years 2002 and 2003.

And if you want some really useful advice about those earlier vintages, you'd do well to pick up the new edition of a book I praised to the rafters last year. Wine Report 2005, written by a group of specialists under Tom Stevenson's editorial direction, is the most useful book imaginable for drinkers who want an up-to-date picture of the wine world that focuses on big issues rather than specific buying advice.

The specialists have no qualms about laying into dodgy or doubtful practices. The section on northern Italy speaks of the "ignorance and incompetence" of official tasting commissions. The 2001 vintage in champagne: "dilute, insipid, and unripe. Anyone who declares this vintage needs their head examining". Australian wineries are legally entitled to engage in several frankly slimy practices, including applying medal-winner stickers to bottles of wine that don't come from the award-winning batch. And so on.

The book makes for compelling reading, and is all the more useful because it covers a range of non-regional topics including wine on the internet, auctions, science,viticulture, organics, etc. Essential reading for wine lovers.

So, what to drink now-ish rather than later-ish? Well, there's a pretty clear message from Olivier Poels, Wine Report's man in the Rhône valley. He finds himself able to say nothing kinder about the 2002 vintage than that it was "average" in the northern appellations. Even that's pretty generous in my view, and it means that my fellow Rhône-ophiles need to look to the earlier vintages if we're to keep ourselves happy over the next year or two.

Amazingly, one of the best Rhône bargains around is still on the market: the Crozes-Hermitage 2001 of Alain Graillot (one of Poels's best-value producers) for £10.44 at www.sainsburyswine.co.uk. The 2002 vintage of this wine is lamentable; the 2001 is sublime, textbook Crozes. Leap on it. Leap also at Crozes Hermitage "La Matinière" 2000, Domaine Ferraton, a gold-prize winner in this year's International Wine Challenge which sells at Berry Bros & Rudd (tel: 0870 900 4300, www.bbr.com) for £8.04, or £7.63 if you buy a whole case. Look at the online lists of good Rhône suppliers such as Lay & Wheeler (tel: 08453 301 855, www.laywheeler.com) or Adnams (tel: 01502 727 222, www.adnamswines.co.uk). The merchants are all in the process of moving on to the 2002 vintage and, who knows: some may be OK. If I had money to spend, I'd be stocking up on the earlier years just so I didn't get any nasty surprises.

For a surprise of a much more pleasant type, pop into a branch of Asda. The UK chain has, for five years now, been owned by the American giant Wal-Mart, a company that treats cost-consciousness as a religion. But its wine buyers have been allowed, as I predicted, to avoid the Wal-Martizing of their department. Their most recent tasting, first of the London season, showed some real surprises: individual wines of real character. Strengths: South Africa, Chile and France. Three goodies are presented here. Almost worthy of a mention in next year's Wine Report.

Top corks: Three Asda surprises

Cape Grace Chardonnay 2004 £4.48 A nice wine from a South African co-venture sourcing fruit from different producers. Robust flavours of melon and tropical fruits. Low-priced star.

Coyam 2001 £8.94 An organic Chilean, a weird blend (Carmenère, Syrah, Merlot, Cabernet Sauvignon, Mourvèdre) with indecent richness and fine balance. Can't imagine anyone not liking this.

Gerard Bertrand Côteaux du Languedoc 'Les Terrasses Quartenaires' 2001 £6.48 Very well handled Grenache/Syrah blend with fine spice and a hint of mint. Accessible but serious.