Recently people have had issues buying Bitcoins fast enough.
Bitquick.co has been one of the fastest way of buying BTC in the US. They introduced a way for Americans to buy BTC directly with cash deposits into the sellers bank account.
1. Select an order from the current order book, enter your email address and submit.
2. Pay the described sum in cash (physical bills) to the account shown on the confirmation page by going to any local branch of the sellers bank and filling out a deposit slip. How to fill out a deposit slip
3. Upload the receipt to link that is provided in your email.
Bitquick sends you the coins typically within 3 hours of the funds being confirmed by the seller.