Thanks MatHi David,
There are two hotels very close to the bowl. The Hills Lodge is right behind the bowl here is there website: www.hillslodge.com.au. The other across the road from the Hills Lodge is the Crown Plaza Norwest there website is www.norwesthotels.com.au.
I think both of them are more on the expensive side. The other option would be to stay in Parramatta. I hope this helps!
Regards,
Matthew