I haven't ever had one, but I was in Hong Kong last year during Chinese New Year...actually went to Hong Kong Disneyland on the official day of celebration
You may be able to find stuff at party stores for the holiday but I'm not sure, there are some traditional things...red and gold are definitely good to wear, and have around the place. Red paper lanterns are also a good idea if you can find them
Older married people will hand red envelopes with money or gifts inside them to younger, single people per tradition.
It's the year of the Tiger, so some Tiger decorations of any kind would probably be good.
One thing I noticed is that in Hong Kong, they aren't afraid to make it as wacky they wanted to about merchandising for the holiday...since last year was the year of the Ox, there was all kinds of crazy Ox things for sale
I am of Chinese descent, so I may be able to help you too.
Chinese New Year falls on February 14 this year. Yup, same day as Valentine's Day, so unfortunately, you may run into some schedule conflicts. It will be The Year of the Tiger, so you can use a tiger theme.
Red envelopes are a traditional Chinese New Year gift, usually given to children from parents/grandparents/uncles & aunts, and contain a small amount of money.
Chinese lanterns are usually hung, and big feasts and parades with the famous Lion Dance are a big part of the festivities.
I've found a lot of ideas and products from China Sprout: