You can indeed just plug an access point into your switch
I'll let some others suggest which one to get (I used to use a belkin one) - but I now have a wireless router.
Here's the one i had for example.
http://www.ebuyer.com/customer/produ...duct_uid=31034
It also depends what speed your wireless card is? if it's only a 'b' one then you could save a few quid i guess and get a 'b' access point - but to be honest I'd get the 'g' one in the first place