ebay has thousands of those and if you know what you need - good deals can be found.
Most people buy and don't equate the purchase to their need.
Playing on the web, playing music, doing light photoshop etc - requires almost no computer. You could buy a new low end netbook for $200 - hook it to your monitor and be happy and portable. They are much better as a music player than an ipod (but a bit larger).
Go to Newegg and buy a 'barebones unit'. You can get them as bare or as loaded as you choose. To be honest, with 10 minutes of reading - sticking in a hard drive, CPU, memory, etc is as easy as changing batteries in a flashlight. You could take those from old broke computers you might have about, or buy new ones there. You not only save a lot, but just get to buy what you need.
Also, you can buy open box stuff there and on similar sites.
The trick is to figure out what you expect of that computer. Unless you are a gamer, you don't need much to be happy. If you are a gamer, you can just buy the upgraded parts you need.
Word processing and web play needs almost nothing.
I have too many computers, including the one I am typing on here on my deck. This is a tiny ASROCK about 3 inches high I built. The CPU is last year's slow as hell n model HaHa. You would think it could do nothing - but it sits out here on the deck and upgrades my weather station to the web 24 hours a day.
Also, it allows me to run my blog
And also to play music as I do all that. In fact, I challenge all here to find a better music server than this.
Inside the house I have multi core - puters that do other things. This is a good one though, costs little and works all day everyday through heat and cold.
Excellent computers can be had for less once you decide their task.
You are wise to search for a used one. Actually, these days I am contemplating on one to hook to my new LED TV. There again - video play requires almost no computing power - so again I am looking at small case solutions but with HDMI and 1080p as that will be needed there. Decide what you need, and then you can shop wisely.
If you live near me - be glad to come over and help.
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