A book you might want to consider is "The Indispensable Composers" by Anthony Tommasini, who is the chief classical music critic for the New York Times. It’s a brief history of classical music, roughly in chronological order, with lots of suggestions for what to listen to. It focuses on his favorite composers and types of music, so it leaves out a lot and you wouldn’t want to limit yourself just to the things he recommends, but it’s a good starting point.
A good website for reviews of recordings is ClassicsToday.com. If you want access to all the reviews you have to pay an annual fee, but a lot of the reviews are available for free.
HRAudio.net has reviews of hi-res recordings. Most (but not all) of them are classical.
The stores Presto Classical and ArkivMusic aggregate reviews from many sources on their websites.
A good website for reviews of recordings is ClassicsToday.com. If you want access to all the reviews you have to pay an annual fee, but a lot of the reviews are available for free.
HRAudio.net has reviews of hi-res recordings. Most (but not all) of them are classical.
The stores Presto Classical and ArkivMusic aggregate reviews from many sources on their websites.