1) You will need a print server, as it has the necessary firmware and software controls for managing the flow of data into the printer and printer comminications back to the source. A plain USB wireless adapter cannot do that.
2) USB Printer servers come in wired and wireless flavors. For best performance, I recommend you should use a wired model. This gives best speed between the network and the printer and it keeps the printer communications from burdening the limited bandwidth of the wireless portion of your network. (Remember, the printer data must traverse the wireless network twice - once from the host to the router, and then back out from the router to the printer.) Physical configuration is easy - an ethernet cable from one of the unused ports on your broadband router to the print server, and then plug your printer into the USB port on the server.
If for whatever reason you can't put another ethernet cable between the broadband router and the printer, then you can use a somewhat more expensive wireless print server. As with the wired model, the printer plugs into the USB port on the print server, but the connection to the network is via radio signals to the broadband router.
I have a Canon MP730 4 in 1 printer that uses USB to connect to my desktop PC. I am using a D-Link wireless broadband router for my wireless network. My desktop is connected to the router via patch cable, but my 2 laptops are using D-Link Wireless cards. I want my laptops to be able to share the printer, so I thought about getting a wiresless print server. But with the Canon printer using a USB cable for commumnication, cant I just get a USB Wireless adapter? Its a lot cheaper than the print server. Any suggestions???? I am running Windows XP on all PC's.