now i have made my own auction script for Argentina, investing about 30000 usd dollar now we have 3 month live , with 500 users and 25000 products! www.remateglobal.com
try itechscripts.com their product is good...I had bought exact quibids from them in d beginning it was little harrasing but later on their product and after sales service was very satisfactory
AJ Auction system is now updated and it is now available with advanced features. Get AJ Auction 2012 for more auction site facilities.
Use Wordpress with this Sitemile plugin (check the demo!) http://sitemile.com/products/wordpress-auction-reverse-auction-theme/ Wordpress is easy to use, friendly and very stable (used on millions of sites) and constantly under development.
I have a site running phpprobid - fruit-machine-sales.co.uk - and for the money, you probably won't get anything much better. Especially considering you only have to pay once for the license but then get ongoing support FOC.