For Diana's methods, buy her book, I linked to it earlier in this thread. It has been a constant source of reference for me. Others here can point you in the right direction for the other methods. You may be able to Google 'em, as I do remember seeing them listed on a site/forum at one point.
I have tried to strike a balance with Walstad's methods and the high-tech, and have so far been lucky. She uses soils for the substrate, I chose Flourite (before I bought her book). I inject CO2 in my heavily planted tank, and I like the fast growth. My other tanks grow plants well, but they were not originally designed as planted tanks. I'm slowly trying to retrofit them.
Here are some of Walstad's methods, which she backs up with scientific data in her book:
-Soil can provide a long term source of nutrients to your plants roots. Flourite can provide some nutrients over time, especially Iron, but it's major benefit is its ability to hold on to nutrients since it is very porous.
-She does not inject CO2 or add micro-nutrient fertilization, instead uses overfeeding of fishfood and its subsequent decay and conversion (by beneficial bacteria) to provide both. She claims fish food is the ultimate fertilizer because it contains all the nutrients our plants need, including carbon once it breaks down and settles in the substrate. Look at the nutrition stats on the back of your fish food when you get a chance, she has breakdowns of the micro-nutrients in her book.
-She also believes most tap water contains enough nutrients to benefit plant growth. Algae growth is evidence for this as it could not grow without an excess of nutrients (of which it is better equipped to consume, so adding ferts can also better feed algae).
-She encourages putting tanks near windows to benefit from sunlight, but concedes that this can promote algae and suggests blocking sunlight from reaching the substrate and filtering light from the back of a tank if algae becomes a problem.
-She concedes that high-tech tanks work very well for most, but that they are cost prohibitive, and require a lot of maintenance.