heres how it works:
you gotta pay for your bids...say 50 bids for $75 bucks...and you can use these bids against any item up for bid on the site...each time somebody bids it raises the price of the item by a penny
bidding on an item also resets the "tick time," which is a countdown from a predetermined amount of time to 0...if you are the winning bid when the clock hits 0 you win the item
these sites are basically a scam, as your odds of winning are extremely slim...the only good thing is that new variations are coming out every day - so if you can find a relatively new site with a low volume of traffic, you might be able to snag something
also be carfeful as a lot of these sites have bots that go around and randomly bid on items to jack the price up (think about it...if an item sells for $40, the company gets roughly $1 for every cent of that $40 - not to mention the other money spent on a bid pack not used on that item)\
one of the first sites that most people base their own off of is bidstick.com...i tried it out on that site and wasted $20 bucks...people from all over the world can bid on most of these sites so there is really no "down time"