What is the best dock for connecting a laptop and ipod to speakers?

What is the best dock for connecting a computer/laptop and an iPod/mp3 player to speakers via RCA cables? I really need a dock like this for a party and I only have a dock for connecting an iPod to some speakers via rca cables and really need to be able to connect a pc laptop/computer to them as well. I don’t really want to spend more than £30 and if there is something on AmazonUK that would be great because i trust that website.. Please answer my question!
56 minutes ago – 1 week left to answer.
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I have just found this apple dock; http://store.apple.com/uk/product/MB125G…
Can you connect a laptop/computer to this?

This :

http://www.thegreatguys.com/servlet/the-16569/Boston-Acoustics-Horizon-Duo-dsh-i/Detail

Thanks

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