I agree with many of the rec's above, especially Smitten Kitchen - not just her books but her blog, which has a million recipes. (EYB, you can correct me on the count)
If you watch Ming Tsai, he has a great website as well, but his Simply Ming: One Pot Meals is wonderful, low key and easier than Blue Ginger (which I had the pleasure of eating at before it closed).
Two of my go-to cookbooks, evidenced by stains on the pages, are Patricia Well's Trattoria and Bistro Cooking.
Another website that is fabulous, if you like baking, is the King Arthur Baking site. They have a ton of recipes, advice, and honest reviews. I have one of their books but I get more recipes off their website. And I have been known to reach out to the Baker's Hotline via chat and they are super!
And my next-to-last final comment -- I almost always check out a cookbook out of the library to see if I want to buy it. If there are only 5 or 10 recipes I think I want to make, I bookmark the book as "Library", and know I have to plan ahead to get it. Libraries are the best, and I am fortunate that mine has a well stocked section.
And the best cream of tomato soup I've found is in Barbara Kafka's Soup: A Way of Life. :-)
Happy cooking!