The kind folk over at T-Shirt Magazine realeased an amazing ebook in July to help you launch a rad t-shirt brand. I actually only just came across this, and downloaded my copy yesterday. This bad boy is packed with 241 pages of helpful information and insight to help you out on your journey of starting your own label. There are a fair few ebooks floating around out there that cover this topic, but this is definitely worth the investment.
You can get your copy here.