Speakers, etc for office system

[gtm]

We want to stream music from a central computer throughout the office. We could do this with our previous EOS Wireless system and 5 wireless speakers. However how system died and I'm looking at options. I'd prefer going wired. We have an open ceiling so running the wires would not be too difficult. Would we need an amp? What types of speakers/mounts (durable)? What type of cable? What else would we need? Or would it be easier to just stay wireless? Thanks in advance for any ideas and opinions.