Christmas is less than two weeks away, and today is when people get serious about gift shopping, researchers say.

At least $1 billion is expected to be spent on Green Monday, when online retail sales typically peak.  Ebay coined the term "Green Monday" in 2007 to describe their best sales day in December, the second Monday of the month.

Online spending is up 15 percent from last year for the first 39 days of the holiday season, with nearly $25 billion spent, according to comScore, which tracks Internet activity. Spending has surpassed $1 billion on six days in this holiday season, with Cyber Monday leading at $1.25 billion.

Top Discounts Today:

Sears has up to 60 percent off on over 500 items.

Kmart has up to 55 percent off outwear, sweaters and fleece, up to 35 percent off game room equipment, and up to $300 off TVs.

Macy's has deals at up to 60 percent off.

Gap, Old Navy and Banana Republic online are offering 30 percent off through midnight tonight.

Click here for a complete list of Green Monday deals, and look for free shipping offers from your favorite brands!

If you have your eye on an item that's not on sale today, hold out for Free Shipping Day on December 16, which already has 1,876 participating merchants.

Click here to find gifts that are made in America with our constantly growing gift idea list!