How about IKEA Strikt? They're canvas covered. Comes in four colors. The brown is quite sophisticated looking.

IKEA, Target, or a sale at Container Store.

I love these colorful bamboo baskets.
http://tinyurl.com/33yp4f

If you're REALLY on a low budget, it's hard to find anything good for a price that is still affordable X 10.

I would recommend getting 10 cardboard boxes in your desired size, and some large pieces of decent looking fabric (try a thrift store), then wrap the boxes neatly, folding around the corners like wrapping a present, and staple the fabric to the boxes. Or use contact paper (possibly harder to get looking nice.

Then you can save up for the more attractive bins.

You might even have some luck trying the dollar store or Wal-Mart (which I hate, but often have cheaper solutions than Target).

Also, to decrease the cluttered look, I'd turn the magazine boxes around (we've got the same ones) -- which may not be practical for everyone. I've also bought some pretty paper that I plan on (one day) covering just the front panel with and adding pretty labels.

I second the Strikt boxes from Ikea. I use them in my bathroom in purple and brown, inside a white shelf, and they look great.

Target also has great-looking black "leather" straight-sided boxes with contrast stitching; I like those too.

What if you replace the shelves with enclosed storage (something along the lines of a shallow ikea pax unit with gloss white doors). Rather than spend money on expensive boxes, you can keep your things organized as they currently are, and simply close the doors for a neater look in the office. This could probably be done for around the cost of 10-15 pricey Container Store cardboard bins.

magazine bins (Princeton Steel Shelf Files) from a school library supply company. Durable and sleek. I have them in red without the felt base.

http://www.highsmith.com

the beauty about ordering from them is that they offer a volume discount for 12 or more.

I second AmericnJewl's comment about turning the boxes around; the bottom side has more metal surface area to cover the contents of the box when it's displayed on the shelf. However, if you choose to turn the boxes around, you'll need to use something to cover the raised metal label area, otherwise it might scratch up your shelf surface.

just turn your open bins around so we see the back (higher) side. then it will look like one black shelf instead of the cardboard with stuff inside.

I agree with Joan V that you should turn those magazine boxes around and maybe you can get fabric storage cubes like these for the other shelves..

i recently picked up a set of three from walgreens for $5

Wooden wine boxes

Christmas Tree Shop (there's one in Paramus near Ikea)

I think the magazine files actually look fine (bsc's fabric idea sounds cool though), it's the other stuff that seem cluttered. Maybe not using the side shelves for the files and using the shelf above instead, it might give a more balanced feel. Nice looking storage boxes might help for some of the other things.