The new Dell notebooks have an option of getting an Intel Wireless-N Mini Card. This supposedly requires a 5 Ghz router, and the only router I could find was the Buffalo Nfiniti one. I'm not willing to spend $250 on a router. Are there any other options? Should I just get a cheaper router and not use the card I got with the laptop?

Well draft n cards are supposed to be backwards compatible with g. I would be surprised if it wasn't since then it wouldn't work in public wifi areas or offices. The 5 ghz is just a cool option to avoid interference. It should be able to run 2.4 ghz and 5 ghz to compatible with all the other draft n stuff. Just run a little more research on the card and figure out what it can do. I agree $250 for a router seems high. I suggest

BUFFALO WHR-HP-G54
hacked dd-wrt with alternative firmware for distance
available $56 http://www.newegg.com/Product/Prod [...] 6833162134

or

I use DI-634M which has excellent throughput at short range with super g cards. They don't make them anymore but with dlink you have to be careful cause some of the unreviewed stuff might not work as well.

http://computers.pricegrabber.com/ [...] 95/search= DI-634M

Thank you for the great answer! I will after all get a 2.4 GHz router, as on Intel's website, the info says that that adapter works with both types of routers. I don't really need distance, as the farthest I will be is my backyard, which will be 200-300 feet from my router. That's kinda far though, haha.

I already have a router though, can't I just get an access point?

Yes use an access point or you can wire your router to the lan port of another router and set the ip to be in range and disable dhcp. I find routers can be cheaper than access points. But I'm a cheap college student who just sets this stuff for other people.