C.T.
Look up a company called MyZeroRez.com and look for someone in your area. I had them come out last year to work on my 12 yr old carpet and they really got the carpet clean. It was even fluffy again - even the stairs.
I found that the RugDr worked well enough but they leave a residue that attracts dirt on the carpet. If you go that route - look at it before renting to make sure it's clean.
Zero Rez was well worth the money -