First off welcome to a.net.
You can try http://www.plane-mad.com/
for frequencies. Go to airport guides. Belfast City appears to have Tower on 119.20 and Approach on 130.75. You would be best to try Tower if you live 5 miles away. Approach might be harder to get. You might have to add a zero to the end of those for the AR
108. I have that scanner but I can't remember how the frequencies go. I'll have a look in the morning if you like.
Hope this helps a bit.
Failing doesn’t make you a failure. Giving up and refusing to try again does!