This really isn't that difficult and you can do it on the cheap if wireless isn't critical to your small business. Just buy 1 wired router with a built in DHCP server, and 4 or 5 wireless ones. Unless you need them to be powered by PoE, I wouldn't bother with the Cisco Aironet APs, just buy some cheap Linksys/Cisco wireless routers. Once you have all that, setup your wired router to connect to your network and then configure the wireless routers in the following way:
1. Disable the WAN/Internet interface on each one, you won't need it.
2. Give each one a static IP inside your network on the LAN interface (for example: 192.168.1.200 - 192.168.1.205) with a gateway equal to the LAN IP of your wired router (for example: 192.168.1.1).
3. Set each wireless router to have the same SSID, encryption, password and channel (disable automatic channel selection).
4. Connect one of the LAN interfaces on each wireless router back to your network.
Because all your APs have the same SSID and password, the wireless clients should automatically connect to the one with the strongest signal strength. Your connection may temporarily drop if you are downloading a file and start walking across the office but for most people this solution should work. If you require monitoring, use a ping script or network monitoring tool to make sure all the APs are up.
PRTG is actually free for less than 10 sensors so I'd recommend that if you don't already have one.