For guys, a good blazer should go without saying, but it need not be expensive. Macy's has frequent sales and good merchandise. Some of us might have to visit the Men's Wearhouse, or a "big and tall" specialty store, to find non-standard sizes like my 48S. The first choice is navy blue, though I personally prefer midnight blue, and then true black. Pick your colors carefully: the Ivy League look of blue jackets and gray pants is fine, except if that's what your building's security guards wear. No choice of tie can change that similarity. So go for a blue jacket and olive pants (very popular now), and a black jacket goes well with tan pants.
Ties are how a guy can make similar wardrobes, even the same, look very different. This is particularly true if you don't usually wear a jacket around the office. One good blazer should go without saying, and I add that one good blazer and five good ties are better than a few mediocre blazers and just a couple of ties. School stripes might be a bit too preppy depending on how conservatively you dress, but you can never go wrong with subdued repeating patterns. A new trend is a semi-plaid pattern with heavy diagonal stripes in the traditional direction (down from the wearer's right in the U.S., and the reverse in the UK and much of Europe) with criss-crossing pinstripes.
A fellow stopped me the other day in the Times Square subway station to ask where I got my medium-green tie and matching handkerchief. They're what I wore last St. Patrick's Day. Depending on how I rotate through my other ties, I wear them about every two weeks with matching green cufflinks, a white shirt and black suit. It seems that combination always garners compliments from someone, as does the red tie with black pinstripes that I got for Valentine's Day. That I pair with a solid red handkerchief, adding a little flair that in recent years is no longer old-fashioned.
I personally dislike sweaters. They're good in a more casual environment, but in a business setting where neckties are standard (not just "often required" like the article says), I find them suitable only for preppies or older men. Regardless, they are most certainly not James Bond, except for the one scene in which Roger Moore wore a totally 1970s look: blue blazer, gray pants and a white turtleneck. Other than that, Bond wears great suits or jacket/trousers combinations, with or without great ties, but not sweaters. Forget what Daniel Craig wears -- that man has single-handedly ruined the legacy, more than any of us initially feared.
Whew, if this isn't my most metrosexual post ever...