The best thing you can do is decide what you want in an mp3 player.
How much storage? (a flash player that can hold a few albums, a hard drive player with the potential to hold your entire collection, or a mini-hd player as a compromise)
What will you use it for? (hard drive players don't go well with exercise)
What's the format of your digital music collection? (if you have iTunes store songs, then you'll have to use an Apple player, not all players support ogg vorbis or flac, but mp3 is almost universal)
Is your digital music collection tagged correctly or is it pretty messed up labeling? (if it's tagged well, look into id3 tag database oriented players that read the tags, if not, look into file folder tree navigation players)
Do you want any special features? (fm radio, recording, etc)
How will you be listening to it? (out of the line-out with an amp or straight out of the headphone jack)
How big (physically) do you want it to be? (a lot of the older hard drive players can be found cheap, but they're usually huge. flash and mini-hd players have a definite advantage)
And finally
How much are you willing to spend?
These are just a few questions that pop to mind. There are many more. Decide what you want and which ones are the most important to you. Only you can decide what's the best for you. I find preference to be highly subjective. Use the search function here, and
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