It's easy enough to find an mp3 player. But when you add that you want a docking station so that you can connect with audio system AND charge the player, that's when things get more difficult. Unfortunately, because iPods are the most popular players in terms of sales, most manufacturers will focus making accessories for them.
Anyway, it's all about the data port on the mp3 player. This is the point at which almost all mp3 players charge as well as transfer music. And iPods have a proprietary data port, which is why docking/charging accessories don't work with other players. Most of the time you can use such accessory with other players if they have an aux input, but then you don't get charging. A lot of players have a mini USB or USB type connector, but I don't see a lot of acceptable docking accessories. Actually I can't remember anything off the top of my head. Maybe someone else can come up with something.
However, I will point you to the Sony players. They are not that cheap, although you can get the more than capable E436 for $80-$90 for the 4GB model depending on where you get it. I just bought one myself at Best Buy a couple of weeks ago. Pair that with a Sony docking cradle that you can hook up to your home entertainment system so that you can charge and play tunes at the same time. I will give you links to take a look at both. Now the docking station doesn't list the E436 as being compatible, but that player and all of the players listed as being compatible have the same type of data port (also proprietary) so you should be okay.
Also the E436 plays video. I realize that audio is all that you really want. Just don't utilize the video function. You're not necessarily paying more to get that function. Yes, you can pay less for players without it, but not much less and you will lose the ability to dock it.
Sony Walkman E436:
Sony Walkman Cradle with WM-Port:
You can also navigate around the site to take a look at other players and options Sony has to offer. If you are anywhere near a SonyStyle physical store, it's a great place to look.
Looking for a MP3 player for my husband that he can use when he runs and then bring home and dock into a device that will charge it as well as stay connected to a receiver or speakers that we already have in the garage. I would like to spend under $150 for the MP3 player alone, preferably closer to $100. I don't really understand about the docking stations and what will charge which MP3 players (except iPod of course) and which you can hook up to home entertainment systems without draining the batteries. Looking for 4-8 GB nothing fancy and simple to add music. Other than iPod the only other I found with a docking station and a home A/V pack was the Zune. Any opinions, anything less expensive