hey i was just in your place a couple weeks ago and i found this one:http://www.xoxide.com/moneual-wireless-keyboard.html
plug and play in both vista and xp and it's only $30 bucks. the quality is good and best of all it has a trackball so you don't have to worry about a mouse (which i really like). The range i'm using it is at about 12 ft with no problems.
if you have more money the logitech DiNovo edge is very nice and has a laptop style touchpad, it's bluetooth and i haven't used it but it also has good reviews.http://www.newegg.com/Product/Product.aspx?Item=N82E16823126008