I have 2 scars on my left leg that are a light purple and light reddish color and would like to know what kind of make up or concealer would help to make them less apparent. {scars are about 18 years old} I also have some new scars that are from having skin tags removed 4 months ago. They are light red. What would help to cover them up? Any info. Would be greatly appreciated! :o

You could get help from a dermatologist and also use Vitamin E on the scars.

For temporary effect, you can apply some cosmetic lotion like - foundations / gel .
You can hide scar by appropriate clothing.
If you want to remove scars prmanentely you can use " SHEHNAZ HUSSAIN'S lotion , you can get it any where from India, or can search from Google.
You can use some herbal treatements like - apply tomato crush on the scar regurlay , it will vanished but took long time to go.
There are many home recipies are available but you need lot of patience & took long time to heel .
Choice is yours..

I would advice not to use any synthetic or chemical application. That would cause harmful effect on skin and further increase other problems.