The Venetian is pretty close and definately is the nicest casino/ hotel out there.
Room rate will run about $200 USD per night.
The Westin is nice too and costs about the same. No casino inside though.
If you are looking for something significantly cheaper... There are plenty of hotels that will charge around 70-80US per night.... But you will most likely need someone who knows the area to book it for you. The Taipa Square Hotel sounds like one that falls into the following category. You can also try 'Kingsway Hotel' which is located closer to the Sands and the Wynn.
This link gives a pretty good idea of what cheaper locations there are to stay:-
http://www.hotelclub.net/hotel.reservations/Macau.htm