The Yarra Valley
Since I am no longer there to take you all on winery tours, these are my suggestions for a DIY tour.
There are two possible directions for a tour: either along the Maroondah and Melba Highways around Healesville and Yarra Glen; or the Warbuton highway through Seville and Upper Yarra. Each direction has its own advantages: Warbuton is less frequented by tourists, passes through Orchard areas where you can get fresh cherries etc. in season and also has a trout farm with fantastic smoked trout. Warbuton is also a nice town, with platyuses occasionally to be seen in the river, the old mill tourist centre, a good bike track and nice forest.
Healesville has the advantage of several good restaurants, the wineries are a short drive from each other and it has of course the Yarra Valley Dairy.
I would recommend that you stick to 3-4 wineries per trip. Maximum 5. I once did 7 (well I could only remember the names of seven by the end), but everything starts to taste the same at some stage. On that tour one of my friends fell asleep on the back seat and refused to get out of the car for two of the last three wineries.
A good time to start is around 11 am, most wineries open at 10.30 and it gives you time to see one or two wineries before lunch.
Tour 1
The 'first time tour'.
This is the standard tour with the wineries that have to be done once. I would recommend beginning with the 11am tour of the Domaine Chandon champagne cellars. In the 80's it became evident that the area Champagne would not be able to produce enough sparkling wine to supply the worldwide demand, so Moet & Chandon, the producers of Dom Perignon, decided to spread out with wineries all over the world. Victoria produces one of the best sparklings in their portfolio.
If you're not a fan of sparkling wine, that's no reason to skip Chandon, as they also make a still wine and most people like their sparklings anyway.
Allow 15 mins along the Maroondah highway from Lilydale, through Coldstream, there is a big brown sign indicating the turn off on the left side. If you're late you can generally catch the tour up if you hurry through the first rooms.
After the tour you can purchase a glass of champagne in the magnificent Green Room, which has a fantastic view over the rolling hills and vineyards. The champagne is definitely worth it, and I can particularly recommend the rose and the premium. It also comes with a bread and cheese platter, which is good for soaking up the alcohol.
At Chandon you can also pick up a copy of the free tourist map of the Yarra Valley with most of the wineries marked.
The next winery is a must, my favourite winery: Coldstream Hills. If you do decide to skip Chandon, I prefer to take the scenic back road to Coldstream Hills: right into Killara Rd, which soon becomes dirt, the eventually after crossing a small bridge turn left (it is better to check the Melways), at the end of the road right. The cellar door at Coldstream Hills has a range of magnificent wines on tasting.
There are two tastings on offer, the free tasting or the $5 tasting (refundable on purchase). If it means that you only do the one winery, do the $5 tasting.
The free tasting covers the basic young wines, whereas the $5 tasting includes the reserve wines (i.e. wines made from the best grapes and from varieties that are not planted in such large amounts)
It is also interesting to taste different vintages of the *same* wine to see the influence of differing climatic conditions.
As a contrast I would suggest going to a couple of small wineries. If you want to eat at the Yarra Valley Dairy, or get cheese and bread or a hamper there, I'd go to Yering Farm: friendly staff, good atmosphere, nice wine and they have fruit in season.
Yarra Track has great views on the way up, a good atmosphere, and when the wine isn't sold out, a very nice pinot noir.
Yering Station has a great range of local produce on saleand really should be seen at least once. Oakridge was always interesting, I'd be curious to hear how it is now under new management from WA. Otherwise on the way out of Coldstream Hills there's Tokar Estate (?) new, with the ambition to create a Rioja style tempranillo, which I'd really like to see. Dominique Pinon (?) on the other corner of the road with Maroondah Hwy is a winemaker's tip.
Food tips for tour 1:
Restaurants
I haven't eaten at many restaurants, but Eyton was pricey with very nice fancy food. The Healesville Hotel (make sure you get the right hotel of the three in town) is run by city people and produces food like Melbourne's fancy restaurant (e.g. trio of salmon entree and quail with bitter chocolate sauce and tarte of baby vegetables, mmmm).
Picnic's
My favourite picnic spot is Badger's Creek, where you can feed the rosellas. Just don't forget the newspaper and matches if you want to bbq. Wood is (was) provided. SImilar style, but less people: the dam up in Christmas Hills, where you can often see kangaroos and watch the sailing club on weekends.
Otherwise St Hubert's has a bbq area with electric bbqs. And Yarra Ridge has a picnic area and some good wines.
Tour 2
Ainsworth Estate: great picnic area and bbq, lovely Jarrah and nice people, oh yeah, and the award winning wines. Seville Estate, one of my favourites only open on weekends, great place for a picnic, with a great fireplace for winter. Then in Upper Yarra, Yarra Burn, who have by reputation good food, nice white & red wines. After that Tommy Finn's trout farm sells fresh trout (for the grill) and smoked trout for a picnic. I'd then suggest Yarra Ranges State Park for a walk/drive/ check out the biggest tree in the state. Signposting's lousy though.