Yes a wireless modem router is required. AOL will tell you that you need to be on their premium service for this unless you buy the router from them. What they mean is they won`t offer support.
A USB wireless adapter will do it and this is what I`ve used successfully with an AOL account previously. click here The adapter is bundled with the router. You can take the collect from store option and save yourself some money by ordering on line and collecting at the reduced price.
Almost any good router will do it, you just need to go into the AOL Expert Settings to change the router details. If you are happy with the Belkin gear stick with it. The instructions for the D-Link aren`t good but we have managed to "talk" people through it on this forum.