You could also try this book about the heat transfer industry:
TLM Supply House presents I Made That!, the How-To book for setting up and running a heat transfer business!
Also, if you come across a term you don't know the meaning to, you could try the "glossary" search tag here:
http://www.t-shirtforums.com/tags/glossary/
Or the SGIA glossary:
SGIA Glossary of Terms
Or just search google for that term and you'll find an answer.
The more threads you read though, the more you'll understand the different terms used and how they apply.
If you need a term defined and you can't find an answer, go ahead and post a request for a definition/clarification. I'm sure there are others who are reading who have the same question you do.
If you post the question and get answers, you'll not only help your own learning, you'll help those who come after you and need answers (but my be shy about asking)
T-Shirts for Dummies? 
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