My motherboard came with the bridge. Honestly though, you may consider returning those cards and grabbing an ati 4850 or 5750. A 4870 would be stronger than either of those if you can afford it. But I think you'd be happier with a single stronger card.
Regarding the bridge though, you may be able to pick one up online. Also be sure the power supply is able to handle both of your cards.
How can I bridge two PNY VCG951024GXEB GeForce 9500 GT cards?.
If SLi is anything like CrossFire the each card will sometimes/usually come with the bridge. If not, you have to buy them individually off ebay, or someone may actually sell retail versions. Also, if you have friends with cards sometimes they will have extra bridges.
I bought two, ...
I'm sorry you did that. Even overclocked, two 9500 GT in SLi underperform a single 9600 GT.
Consider buying a single 9600 GT, HD 4670, or HD 5750.
Thanks for the input. I have returned the 9500 GTs and ordered two to the HD4670s to put in crossfire. Appreciate the help.
An HD 4670 CrossFire barely outperforms a single HD 4850 (1-2 FPS) which only costs $100, instead of $130+ for two HD 4670. Is there a reason you need to have CrossFire or SLi? It's only useful for high end cards. The lowest I'd recommend CrossFiring is an HD 4850 or GTS 250/GTX 260. Just get a single HD 4870, that seems to be around your price range judging on your choices.
Right, I would cancel the order on the 4670's. Also, keep in mind if you have an sli motherboard, you cannot run crossfire on that board. The reverse is true as well, if you have a crossfire board, you can't run sli on it as far as I know. These technologies are essentially the same, but from different companies. That's why we recommend one stronger card such as the 4850. Though if you are going to spend 130 dollars you may consider this card.
It's close in performance to the 4850, but will give you compatibility for newer dx11 games. But you can get the 4850 cheaper. But as mentioned before, 4870 is a great card as well. Either way, any of the options here should make you a very happy camper. Honestly I recommend a single stronger card over sli/crossfire because you avoid more driver and compatibility issues, and don't have to worry whether or not a game supports those features or not. Should be more plug and play in my opinion. Just make sure your power supply can handle whatever card/cards you are putting in.