Best Buy, Newegg, Staples, Office Depot, even Walmart.com
Web sites like slickdeals.com advertise all the special sales.
Our kids both went from heavy laptops to light netbooks and heavier monitors that remained on their desks where they lived instead. They really didn’t like toting about the laptops, especially the bigger, heavier laptops. Their laptops breaking provided both with the perfect opportunity to make the switch to the lighter machines which were MUCH more portable.
I second what SlackerMom and HImom said. I got sick of my heavy laptop and now commute by with my lightweight Surface - it is a feather compared to the heavy Dell I use at home.
Personally, I only bring my iPad mini and the keyboard cover when I travel. We’ve stopped traveling with laptops, tho H did bring the Surface Pro 3 with the flat keyboard on a recent trip. We really like the lighter weight and portability over whatever slightly more functionality we MIGHT get from a super laptop. IF we need more, we can always choose a desktop at the hotel (or our home).
Check Staples and Best Buy, they should be having sales soon. You can see some display models and you can return to a local store if needed.
Online purchase is the way to go! H and I have bought desktops, laptops, tablets from several of the above sites. Often the manufacturer ahs the best price. Agree about Dell home vs business- need to go to two different sites, though- can’t do a comparison on the same site.
A great site to check on current bargains is techbargains.com (sorry I always forget how to the few times I try to cut and paste). It has links to the websites and coupon codes- changes daily with some deals lasting longer than others. Have used it in the past to find good computer deals on brands we wanted.
Have also purchased TV sets online. Don’t worry about delivery- big ticket items or those commonly stolen usually require an adult signature when delivered. Very secure and packaged well. And- buying from the manufacturer works well. Some other sites such as Tiger Direct and Newegg (and other sites)are great for assorted tech stuff as well. Usually free delivery- be sure to check on that.
Plus- you can usually track your package so you can predict the day it will come. If you can’t be home you usually get two more delivery tries or can pick it up at the delivery place (eg UPS or Fed Ex).
The website dealbuys.com can have some pretty good deals, and I like the format of it, they tell you what is involved, the price and so forth. To be honest, buying online is not a big deal, and if you are worried about support you can always get a service contract on it for when the warranty expires (I bought a computer through microcenter, my son is in boston and they have a store/repair center in Cambridge, and when his laptop croaked after the warranty was done, he got a brand new laptop because they couldn’t fix the old one). Dell is decent, though I will tell you that sometimes they get all fouled up when ordering machines, their sales support is based in India, and the way they have it set up the people there only know what you can see on their website, so if something goes south it is not a pleasant experience (their business services, on the other hand, are based either in the US or Mexico, and I have had great service with either location).
I agree with others, does your D really need that kind of horsepower? With that card, a large screen and a large HD that machine is going to weigh a lot. I would recommend at the least getting a smaller screen (14" maybe) and have an external monitor in her room (they are really cheap now, I bought a 22" Dell monitor not long ago, w HD quality, for like 150 bucks on special). I also would strongly encourage getting a laptop where the main drive was an SSD (solid state drive), they have come way down in price, and they allow the machine to run a lot faster, they boot incredibly fast, and the SSD’s are a factor of many times better than a standard HD. If she needs a larger data storage (I think they have 512 gig SSD’s now), then get an external USB 3 based hard drive for her room, where she can store things like pictures, videos, and so forth and have the main drive have only needed stuff for school.
It may be a good idea to invest in a touch screen monitor if you’re buying one these days.
Yes, it is a very handy feature. Newer laptops almost all have touchscreens. When I switch from my Surface to the old Dell, I often catch myself poking at its screen and wondering why the heck it is not responding to my touch! 
We’ve ordered computers online from Amazon and MacMall and not had trouble. Both in the last year.
I second the suggestion to try and balance weight and power for a laptop.
I agree with nw2this upstream who suggested http://www.newegg.com/ I use our Capital one card for large purchases (when they are not from Costco) because they also have the extended one year warranty, and I’ll get the miles credit. I’ve also been happy with Squaretrade insurance http://www.squaretrade.com/ I went through a roomba vacuum phase and they replaced the cost of two of them with no hassle.
Looking online I came across the Lenovo U31 thin & light laptop. Anyone heard of this? Apparently new this year.
http://www.pcmag.com/article2/0,2817,2487123,00.asp
If you buy one from the school does it include free tech support?
Fry’s and Best Buy will match online prices (including Amazon). Nice to utilize if you’re buying something you may want to return so you don’t have to hassle with shipping. Or if you want something immediately (assuming it’s in stock).
@BunsenBurner How do you like your Surface? DD says several people at her summer internship use them in meetings. When she’s in class she takes her MacBook, but still takes notes by hand.
I like my Surface a lot, but I also prefer to take notes by hand because I memorize things better that way. However, some of my teammates used the provided stylus to take “handwritten” notes on their tablets in OneNote.
@scholarme The Lenovo U31 looks like decent for that price. However, with the i7 and the dedicated graphics card, coupled with an oddly small battery, I think battery life would be an issue. Also, would prefer a solid state drive to the hybrid drive included. Can’t beat the price though!