So I have my 13" Macbook Pro with the latest version of iTunes installed (10.5.2)
I also have a 32GB Wifi iPad 2 with iOS (5.0.1) with the Remote app installed.
I am so frustrate with this stupid Home Sharing. I followed the directions the app gave me beginning with turning on Home Sharing on iTunes on my MacBook with my account. I then used the same account to turn on Home Sharing on my iPad from the Remote app. I wait a bit, and wait some more, and yet my iTunes library isn't shown in my Remote app like it is in my iPhone.
I've tried to find the answer to my problem via Google and these Apple Support Communities, but with no fix.
I wish you could just connect your device to the computer and punch in the 4-digit code like they used to have you do.
Try turning Home Share off then on on the MacBook Pro and then check Remote App to see if now appears and you can connect - for me it works but eventually I will have to repeat the process to get it working again.