If you lost your W2 for 2009, you should contact your employers for copies. If you lost your prior years tax returns/w2s, contact the IRS for transcripts of your returns/W2s.
Your first option is to contact those employers that you had W-2s for but you now do not posses. Your second option is to call the IRS and ask for transcripts. The only problem with this is the IRS does not keep track of your state records. Your third is option is to file a substitute W-2.