This is likely what you are looking for—sites that host or link to iTunes rips. These sites typically source new releases quickly, offering high-quality M4A files with metadata included.
Note: These sites operate in a legal grey area (or illegally). They are often ad-heavy, and domains change frequently to avoid takedowns. Always use an AdBlocker and antivirus software. itunes plus aac m4a sites top
Note: Due to Apple’s shift in business model, there is no longer a "iTunes Store" desktop app. These sites represent the current legitimate ecosystem. This is likely what you are looking for—sites
1. AT Music (and similar blogspot/wordpress sites) There are several high-profile music blogs that focus exclusively on iTunes quality. itunes plus aac m4a sites top
2. LKMusic (and similar indexing sites) Sites like LKMusic (and previously popular ones like K2NBLOG or AlbumKings) act as aggregators.
3. BeeMP3 / MP3Juices (Search Engines) These are not hosting sites but search engines.