If you want to get professional, you will:
1. build the card n-up on a sheet (unless your service provider does imposition for free)
2. avoid the use of bitmapped box frames, which look VERY bad at high resolution
3. select your colors from a swatchbook printed on coated or uncoated paper, depending on the stock you will use
4. select a typeface more readable than Avant Garde (how about Futura -- it's a clean, spare face and not as overused as Avant Garde)
5. have a company logo!

Amateurish article for amateurish results. So superficial as to be next to useless. What was left out, and could have so easily been included, is mindboggling. PMS colors vs. process colors. Cost considerations in using color. Cost effecient layouts. I could go on and on. This piece belongs in MacHome Journal, not on a site called creative*pro*. "If you're outputting the cards to a desktop printer..."? Reeaalll professional...Next time get Constance Siddles to write a decent piece for you. A perfect example why a lot of prepress professionals condsider half their customers to be "Duh"signers...

JeffM.