My first grow I grew some bagseed Afghani Trainwreck, and it turned out pretty good. However, I'd have to side with Brick Top. Buying from a reputable seed co. will guarentee some good genetics. If you're willing to dish out some money, I'd recommend Northern Lights from Sensi Seeds. I've grown this a few times. She grows really strong, is an awesome smoke, and yields good. It's a great overall plant, especially for beginners; and once you get a strong mother plant, you can take plenty of clones off her.
My best advice is to do some research and ask questions to find out what suits your needs best. Good luck man!