It sounds like your parents entered the U.S. lawfully with nonimmigrant visas that permit them to work here. Assuming that is correct, when you reach age 21 you should be able to petition for them to adjust status to become Lawful Permanent Residents (get a "Green Card") in the Immediate Relative category, for which there is no waiting list for visas.
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David N. Soloway
Frazier, Soloway & Poorak, P.C.
1800 Century Place, Suite 100
Atlanta, Georgia 30345 www.fspklaw.com
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