1st off, Hi! Welcome to the "Dark Side"... Fishing itself is is quite addictive, but once you catch your first fish on a lure or soft plastic you made, poured or painted... WELLLL There isn't words to describe the feeling inside... I'm very very sure most of these ladies and gents on here would agree.
As to your questions, I would suggest establishing a feeling for the type of fishing your looking into. For example, Topwaters, Cranks, soft plastics, spinners, swimbaits. By far the easiest, and least expensive to start off with is topwaters. You can carve a topwater from just about anything that floats, Screw some small eyescrews in and attach hardware and fish. As far as Making cranks from scratch... There are some of the best builders and info on this forum that it will send your head reeling.
My thing is painting, and as a suggestion to that side, before jumping into airbrushing, try doing up a couple of lures using sharpies and believe it or not nail polish. They are inexpensive and will give you ideas on color combinations. Spray paints will do the jobs for a lot of lures also, but are hard for details without masking and the such. If you look in the gallery at hard baits you can find so many different styles of lures and paint schemes that you can get ideas from.
The best thing about this site is the info, ask questions, read the past topics and find your style. There's a lot of good folks on here that are more than willing to help and the knowledge base is only limited by your imagination.
Good Luck and Tight Lines, bb