I didn't think I enjoyed wine at all til I discovered this stuff. Sweet & fruity at a very affordable price point. Although, I'm no wine expert at all. Just very picky and will only drink sweet beverages.
The best sweet-tasting white wine that doesn't have a cheap after-taste that I have tried is Cooper's Hawk Passion Fruit white wine. They also have a Winter White wine that is heated to a warm temperature and it is delicious.
It depends--if you are looking for a sweet white (or red) by itself, not with a meal--look at a good ice wine. If you go to the vineyard area near Toronto you can try some very, very nice ones.
Inniskillin Cabernet Franc Icewine, or their Riesling Icewine are both exceptional--but expensive, about $60-75 for a small bottle.
You can get a nice ice wine for $20-25 in several brands. Here it is easier to get them from Canadian vintners, but there are also German icewines.
Chateau d'Yquem from the Sauternes in Bordeaux, France is the absolute best sweet white wine.
It is outrageously expensive, but other sauternes are great as well.
An alternative is German Eiswein, also very sweet. About $50 per bottle and up
Messina Hoff makes a great reisling, white. It is called angel. It is very good. I could drink the whole bottle. Their moscato is very good too. Very sweet and affordable. It is made down in bryan texas. They have a winery in grapevine, where you can go taste all the wines they have. Grapevine has alot of places to do wine tastings up and down main street.