If your computer does not seem to be picking up the DNS change on it's own, there are a few things you can try:
1. Clear your browser cache and temporary internet files.
In Internet Explorer go to the Tools -> Internet Options, then click the "Delete Files" and "Delete Cookies" buttons.
In Firefox, go to Tools -> Clear Private Data -> Check Cache and Cookies -> Clear Private Data Now.
Remember to close all browser windows but one while clearing your cache.
2. For windows users, open up a command prompt and run the command:
ipconfig /flushdns
You can open a command prompt from the start menu by selecting the "Run..." menu option and then typing in "cmd".
If we have posted on the boards that the DNS change has been sucessfully made and it's been over an hour and you still are having problems viewing auctiva.com, it's possible your internet service provider (ISP) is not picking up the DNS change. There is nothing else you can do (shy of reporting the issue to your ISP) at this point and you will have to wait for the propogation of DNS to occur. If this happens to you, please post here so we can be aware of the number of users affected.
-Kevin