Hi there and welcome to the Q&A Board,
We tend not to recommend specific cameras though one stands out in my mind if you want to stick with a Canon camera and use a flash. The G7 is an advanced digital camera with manual controls and a hot shoe for an external flash. An external flash will give you MUCH better flash options and quality than photos taken with a built in flash.
It's one of the featured cameras in our Amazon UK shop:
http://www.digicamhelp.com/storeuk.phpSaying that, I usually do not recommend using a flash for most auction photos. If you don't want to buy special lighting equipment, use available light instead.
Fujifilm compact cameras excel in their low light capabilities using higher ISO numbers. Consider the Fujifilm FinePix F31 fd or F30, which have manual controls. If you can wait a little longer, consider the Fujifilm FinePix F40 fd, which will take SD memory cards as well as xD memory cards (SD cards are MUCH more widely used and faster). The F40 has no manual controls though if they are important to you.
Here are some suggestions for taking auction photos:
http://www.digicamhelp.com/learn/products-auctions/If you want more comprehensive information, we sell an ebook on the subject:
http://www.digicamhelp.com/store/auctions.php