Well, your system specs are needed to recommend anything, and give us an idea as to what you'll be using it for, gaming, just surfing, and what type of gaming.
 
BTW, nVidia cards are no more expensive than ATI, it's a very competetive market right now.

fatdragon, as Relic indicated, you should specify the manufacturer of your motherboard, the make (Intel or AMD) and speed of your CPU, the amount of ram you have, whether your motherboard is PCI-e and/or AGP, and the speed of your bus. If you are purchasing this card for gaming - the kind of games you like playing, and whether in gaming speed or quality of the graphic image is more important. These are all factors in deciding about a new video card.
 
Again, as Relic indicated, don't judge a card by what the "hype" says about it. Some video cards work with some motherboards better than others. The same can be said for games - clearly some games are biased towards one card than another. And, some games require sheer computing horsepower than just a fast card.
 
One thing you might want to do is examine a webpage like MadOnion: http://discuss.futuremark.com/forum/wwwthreads.pl and read what gaming "fanatics" say about their "rigs." You don't have to limit yourself to webpages like this, but they do speak their minds without pulling punches. Since those folks fiddle with video cards the way no stock reviewer ever would, they push the limitations of their video cards that you might find interesting - that is, if you are buying the card for gaming.
 
You might also want to mention some of the cards you are most interested in purchasing. There are a lot of people on this board that have one or another of those cards who can tell you their real world experience with those cards.
 
Hope to hear from you soon.