Until you get a good grip on how the plastic and heat relationship works, use stabilizer at a rate of about 20 drops to a 4 ounce batch. Until you know how to get the heat to 350 without singing your whites, do small batches of 4 ounces or less, stir after 30 seconds in the oven, again at 1 minute, and then reduce the power to 80% and heat/stir for no more than 15 second increments until you get to 350 and then do your initial injection or pour.. Keep your plastic under 350 if you need to reheat or remelt. Don't be afraid of stabilizer as it can save you a lot in time and $$$.
Shane has done a great job of outlining what most of us consider "basic" needs, but if you want to limit your activities right now to white, have at it. There is no harm at all in keeping your focus on a small target to start and maybe its even wise.
Andrew mentions the 360 degree plastic hurting. Its fact. Read the cautionary posts pegged in each section.
Most of all, have fun with this. You'll screw up, we all have and will again. That's part of the program and can actually turn into some great laughs. Everyone is different in how they approach the world of plastics and you'll find your niche and take right off. Don't get discouraged and do not get in a hurry. Remember....good things come to those who wait.