Balloon sizes and colors are ever changing.  This was current in 2007 but does give a nice over view of sizes and colors.

The following sizes are available in Standard Colors:
11″, 16″ and 3′ Giant Rounds are available in all Standard colors
6″ 11″ and 3′ hearts are available in Pink, Red & White
260Q and 350Q are available in Pink, Pale Blue & White
 

The following sizes are available in Contemporary Colors:
11″ 16″ and 3′ Giant Rounds are available in all Contemporary colors
 

The following sizes are available in Jewel-tone Colors:
11″ 16″ and 3′ Giant Rounds are available in all Jewel-tone colors
18″ Rounds are available in Diamond Clear
6″ and 11″ hearts are available in jewel-tone assortments and special red + white + pink assortments
260Qs are available in every Jewel-tone color
16″ GEO Donuts and 16″ GEO Blossoms are available in Jewel-tone assortments

The following sizes are available in Light Pearl-tone Colors:
11″ and 16 ” Rounds are available in all Light Pearl-tone colors and assortments
6″ GEO Blossoms are available in Pearl-tone assortments
30″ Giants are available in Gold, Pearl White, Pearl Mint Green, Pearl Light Blue, Pearl Pink, Silver & Ivory

The following sizes are available in Deep Pearl-tone Colors:
11″ Rounds are available in all Deep Pearl-tone colors
16″ Rounds are available in Pearl Magenta and Pearl Teal

Qualatex balloons are made in America from natural latex and are fully biodegradable.