What could cause a knocking sound under the hood of a car?

I just bought a used 2013 Ford fiesta last month from a dealership. Yesterday, I did a 3hr trip to visit my girlfriend in west Virginia. I pulled off the freeway, because I felt like I was lost. GPS wasn't helping me at all. So, I'm going like 25mph and I notice the knocking sound under the hood. It sounds like it's coming from the driver side of the car. I still visited my girlfriend, but I was cautious all the way home. I only hear it when I first start up the car and at low speeds. When I go above 10mph I can't hear it at all. I got an appointment with a mechanic for Friday, but I work all this week and I'm making another trip to west Virginia on Wednesday. Is it safe to drive or is this something serious?

Which car should I choose?

I'm in the market for a new car. I was recently in a car accident and my car was "totaled" by my car insurance company. Total sham in my opinion, but I'm not willing to fight for the car since I was not "upside down" on the car loan. Insurance will pay the loan off, and I'll get about $600 back.

So far I have been narrowing my search based on price (under $8000), as well as whether or not I like the style. However, I'm not sure what cars have good/best reputations just based on what I've picked out so far… Can anyone help me with this?

1. 2012 Ford Fiesta 90k miles
2. 2007 VW Jetta 95k miles
3. 2007 Scion tC 110k miles
4. 2007 Pontiac G6 75k miles

Will my insurance go up if I buy a Ford Fiesta or Focus ST?

I currently own a 2012 Ford Focus SE hatchback 5speed manual. It's alright I don't hate it and it's great for what it is. I bought it over a year ago so I'm not quite ready to trade it yet but I like to be proactive in the next car I'll buy and I'm just wondering if my insurance will go up considering if it's a sports car? My driving record is perfect and I've been licensed in the state of Ohio for 5 years and I'm a 21 year old guy. My rates now are cheap through Geico (118 monthly) but I recently switched because I paid 230 monthly with State Farm

Ford Fiesta Starting problems?

I have a Ford Fiesta 2003 and it starts perfectly every time. When I start it and turn it off and then start it again, it will start again! However when I drive for example to the petrol station, around 15 miles away, and stop the car and try and restart it won't work? Any ideas?

Ford Fiesta Zetec 1.25 pure white or blue lights?

I've got a Ford Fiesta Zetec 1.25. I want lights that are either pure white or light blue. For the front lights and back number plate lights. But I want legal ones only. Anyone know where I can get some decent ones?