Virgin Megastore, Tower Records, and your local record shop still boast the best and most voluminous music inventories. But with an average 500,000 tracks, online offerings give music-hungry consumers choices galore. So TechTV Labs decided to look at five popular online music shops and services for "The Screen Savers."

Things have gotten a lot better since the early days of pressplay and Musicnet. Today's services offer instant gratification, quick and easy searching, track previews, à la carte shopping, good prices, and seamless integration with your jukebox software and portable player. We separated the services into three categories.

• Website-based stores
  Our examples: Walmart.com and BuyMusic.com
  Web-based stores offer some good deals without any fuss. You don't need a subscription and you won't need to install any special software. Purchase tracks or entire albums and play them back in Windows Media Player or another WMA-compatible player, such as Musicmatch.
  
  
• Software-based stores
  Our examples: iTunes Music Store and Musicmatch Downloads
  
  If you own an iPod or remain loyal to a particular jukebox such as Musicmatch, download a free application and start getting your music. These services are the most typical and convenient. You don't need a subscription.
  
  
• Subscription services
  Our examples: Napster and Real Rhapsody
  
  For about $10 per month you'll get access to a selection of preprogrammed Internet radio stations, receive access to all tracks via streaming, and get intelligent personalization and community elements. However, you still need to buy tracks if you want to burn, transfer, or keep your songs forever. Most subscription services have a non-subscription pay-per-download element as well. If you want to discover new music and artists, or if you like a variety of music, you'll like subscription services.

We tested each service based on the number of available titles, pricing, download restrictions, ease of use, and extra features that set them apart. Yes, we also looked at the portable devices that work with each service so you can know which service to flock to if you already have an MP3 player. You can view our full services and genre search comparison charts on one of the following pages.

Although you won't get to flip through CD liner notes, and your music will include some sort of DRM-protection, most people will be happy with the number of times you can burn, transfer, or copy a track.

Look for Napster and other WMA services to increase the possibility of a format war. Apple uses AAC encoding to compress its digital music, while others, including Napster, use WMA. If you really want an iPod, you're going to have to use iTunes, a choice that's obviously not an issue for the millions of iPod owners. But if you're a PC user who really likes your WMA files from ripped CDs, you should know they're useless on an iPod.