Heya
We built our house with Sovereign Homes. Its an off the plan brick and tile place that we made some changes to. The deal was that there was an "alowance" included for most things, but the allowance only covered the very basic. ie allowances that we extended on were earthworks, driveway, electrical, flooring.
Most building companies has really good websites that will tell you what is included and what isnt.
We really like our house, think it was great value for money (4 bed, 2 bath, 2 living, double garage cost us around $250K to build), and I love the fact that it is new and warm and dry. I have also heard good things about GJ Gardners off the plan stuff. It is probably very area specific though?
Good luck, new house stuff is exciting!!!