Here's how I used to start my seedlings using soil in party cups. You can do well with a simple shop light until you need to move the light 12" away from the plants. Then it's not enough to continue proper growth.
Then I built a sunroom on the south side of my house and found a different way to grow using hydroponics. I can grow these year round with no artificial lights or heat.
I got a bit carried away with it and grew more than I could eat. I really like this method of growing - there are no pests and no dirt splashed up on the lettuce to clean off.