We get lots of questions like this one, from people who don't know what the name of the color is, or from those who just make up a name for their color. Here is a rundown of all available colors on 99-02 Cougars, and their corresponding paint codes from Ford.
Ebony Black - code UB. Available all model years.
Vibrant White - code W4. Available all model years.
Silver Frost - code TU or TS. Available all model years.
Satin Silver - code TL. Only available on 2002 35th Anniversary Editions.
Dark Shadow Grey - code TG. Only available in 2001-2002.
Rio Red - code EZ. Available in 1999, 2000, and 2001.
Laser Red - code HL. Available all model years.
XR Racing Red - code ES. Only available on 2002 XR Editions.
Spruce Green - code FS. Only available in 1999 and 2000.
Tourmaline Green - code NE. Only available in 1999 and 2000.
Grabber Green - code F5. Only available in 2002.
Tropic Green - code SU (also known as Amazon Green in the UK). Only available in 2001.
Melina Blue - code K9. Only available in 1999.
Light Sapphire Blue - code LV. Only available in 2000.
French Blue - code M9. Only available on 2001 C2 Editions and 2002 35th Anniversary Editions.
Zinc Yellow - code B7. Available on 2000 Special Editions, and on 2001 Zn Editions.
Autumn Orange - code BG. Only available in 1999.
Ash Gold - code BJ. Only available in 1999.
Citrus Gold - code B8. Only available in 2000.
Sunburst Gold - code BP. Only available in 2001.
Light Parchment Gold - code BQ. Only available in 2002.
And lastly, a bit of ephemera -
Ice Blue - Only available on the European Cougar ST200 Edition.
Send any errors or typos to me in a PM, and I'll amend this post. Hope this helps; thanks!
Ebony Black - code UB. Available all model years.

Vibrant White - code W4. Available all model years.

Silver Frost - code TU or TS. Available all model years.

Satin Silver - code TL. Only available on 2002 35th Anniversary Editions.

Dark Shadow Grey - code TG. Only available in 2001-2002.

Rio Red - code EZ. Available in 1999, 2000, and 2001.

Laser Red - code HL. Available all model years.

XR Racing Red - code ES. Only available on 2002 XR Editions.

Spruce Green - code FS. Only available in 1999 and 2000.

Tourmaline Green - code NE. Only available in 1999 and 2000.

Grabber Green - code F5. Only available in 2002.

Tropic Green - code SU (also known as Amazon Green in the UK). Only available in 2001.

Melina Blue - code K9. Only available in 1999.

Light Sapphire Blue - code LV. Only available in 2000.

French Blue - code M9. Only available on 2001 C2 Editions and 2002 35th Anniversary Editions.

Zinc Yellow - code B7. Available on 2000 Special Editions, and on 2001 Zn Editions.

Autumn Orange - code BG. Only available in 1999.

Ash Gold - code BJ. Only available in 1999.

Citrus Gold - code B8. Only available in 2000.

Sunburst Gold - code BP. Only available in 2001.

Light Parchment Gold - code BQ. Only available in 2002.

And lastly, a bit of ephemera -
Ice Blue - Only available on the European Cougar ST200 Edition.

Send any errors or typos to me in a PM, and I'll amend this post. Hope this helps; thanks!