Have you been working with this agent a total of 3 weeks and if so when did you submit this offer, or did you submit the offer 3 weeks ago and not heard anything from the agent since?
You also said you signed seevral documents and gave a deposit check so that was an offer ojn a specific property, hopefully an Agency Disclosure, and probably in all that paperwork was a Buyer Representation Agreement which outlines the terms you and the Agent will be working together. This is important because this is the document that ties you and the Brokerage / Agent together and outlines protection periods, etc.
You should have been provided copies of everything you signed within a reasonable timeframe after you signed them - likely about 3 - 5 days.
No one has yet asked - Do you still want the house that you made the offer on? If so, you should contact the Office Manager or Broker and ask to meet with him or her. You can do this a couple of ways. You can ask the agent to arrange a meeting with you, the agent and the Broker or you can call the Broker / Office Manager directly. If you and the agent cannot work out the communication issue, I would suggest you ask the Broker to assign another agent to work for you. The Broker will work out the commission split internally. If you have signed a Buyer Rep Agreement and subsequently buy this house through any agent, the original brokerage and agent will be paid because they were the Procuring Cause - proven by the signed offer.
There is no excuse for lack of communication with a client especially prior to a close of escrow when an agent has taken a deposit. That deposit is either uncashed in the Brokers possession until Escrow is opened, or it has been deposited into Escrow because there's an accepted offer. If it has been deposited into Escrow, and you want out of this purchase, you will need to cancel Escrow which requires both Buyer and Seller signatures - the broker can assist you if the agent cannot.
I strongly suggest you try to work it out and you'll have your new home soon.
Best of luck-
Cheers to you,
Southern California & Houston, TX
2008 Chair, Pacific West AOR MLS Committe
2008 Member SoCal MLS Board of Directors
2008 Member SoCal MLS Steering Committee
2009 Member-elect, Pacific West AOR Board of Directors
2009 Member-elect SoCal MLS Board of Directors