Just wanted to know if there was a way to use the laptop in the car and still be able to access the internet?

The problem here is that you either have to use either mobile broadband or WiFi to get on the Internet. Since WiFi is very short range if you are in a moving vehicle you would be moving in and out of range of a hotspot.

With Mobile Broadband you hook into the cellular network. This will help maintain the signal like your cellphone does, but data is different then a cellphone call. Also Mobile broadband costs a monthly fee.

Yep. Do it all the time.

There are a couple of options:
USB tether
Bluetooth tether

Aircard in Laptop or USB version
A wireless router that accepts an Aircard (multiple laptops)

The USB tether is probably the best option for a single user because it charges the Cell Phone battery and you can make calls while on the computer too.

Generally you'll need a data plan.

Generally, the next problem is power. You can go the 12V to 120V inverter route or get an adapter from iGo.com - Power Adapters and Chargers for Mobile Electronic Devices.

IGo Laptop supplies used to be sold at RadioShack. Their adapters use a multi-input (12V, 120-240V, Airplane) and have a TIP that selects the power and polarity for your device.

The good part is, if you buy another laptop all you may need is another tip.

I have a few complaints with the iGo system:

1. The output cable is rather inflexible. I've had to buy 3 so far at about $20 each in about 8 years.

2. The tips don't positively latch into the cable. I've lost a few at $10 each. I now tape them with silicone tape. About $20 a roll.

3. The 12V lighter plug usually did not make a reliable to the lighter socket. The end can be removed to be used in an airplane. The last time the lighter end broke because of flexing, I replaced the end with an excellent one I obtained from Europe. It claimed it has a different airplane connector. The original cable lasted about 7 years.

IGo is not very receptive to complaints about their products.

I used the end (about 6") that plugs into their TIPS and an extremely flexible cable to replace the DC end of a broken power brick. Same problem. Flexing breaks the coax outer shield. I have been unable to find a power coax connector that will accept a diameter of about 1/4". The cable I am using is a 4 conductor with an outer shield. I did voltage drop calculations and using the 4 inner conductors and the shield would have the lowest drop. I'm using an inner pair for + and an inner pair for - and connecting the shield at one end.

I also do it all the time, I have a aircard from ATT ( got it when they offered unlimited service)

Now it is somewhat costly, ATT and Version offers it locally for about 60 dollars a month