Omg Please Help Me And My Rx300 In Philadelphia Pa!

[TCK]

I own a 2001 rx300 and tonight she just wouldn't turn over. After several tries I realized if the gas is held down the engine will stay running. There was puffs of smoke and when you let off the gas she instantly cuts off. I had to leave my truck at work and get a ride home! I'm not very mechanical when it come to auto stuff. Does anyone know what could be wrong? And how much it might cost to get fixed? Does anyone live in philly that could help for pay of course? Or refer me somewhere? I'm fairly new to philly...I keep up with maintenance and can't afford to spend a whole lot right now. Please help me! :( Any suggestions will be appreciated!