Basically, if you're tired of the expense of liquid ferts, dry ferts are the way to go. GLA has some nice packages, and nilocg sells ferts here (sale forum). And there are other online sources. It's all the same chemicals, so there's no issue of "quality" of KNO3 or KH2PO4 or whatever. There are a number of micro mixes as well (CSM+B, Microplex, etc.). Just pick one - most use CSM+B (Plantex), but it doesn't matter much from a beginner standpoint. If you have low GH, look into GH Booster - that covers Ca and Mg. No need to buy those separately. So, KNO3, KH2PO4, GH Booster (only necessary you have really soft water), and a micro mix. No need for anything else. You'll see that some people use KSO4 for extra K, but it's totally unnecessary in most cases. Up to you, it won't hurt.
If you need dosing bottles, I get mine (and CO2 tubing, and check valves, and some other odds and ends) from USPlastics.