You may not get much information here, but here are my suggestions:
1. Find her licence information here: http://www2.dre.ca.gov/PublicASP/pplinfo.asp?License_id=01280001
2. You need to contact the San Bernardino Sheriff's Department (if the property is in an unincorporated area) or the City Police Department where the property is located. You need to file a report with them.
3. There are very few DRE investigators in California and your best bet is to file with the local police.
4. Without knowing how she collected the money from you that is all I have. If it was sent to an escrow company, then contact them. If you dealt with her alone and sent the money to her trust account, then keep pushing for answers from the DRE, but stand by for a long wait.