Bluth - There are a ton of techniques already out there - you just need to find what works for you. A great place to start is Iyengar's "Light on Pranayama", which is considered a great standard for pranayama work. Yogananda also had some great breathing techniques. There are breathing techniques that are also given through spiritual paths - zen, buddhist, sufi, esoteric christian - and there are various books/websites out there with those also.
Holotropic breathwork is perhaps one of the most amazing breathing techniques because it releases our conflict on the etheric level so that it doesn't permeate to the physical level.