So I'm looking at Barlow's, only site I'm familiar with for now. Should I buy pre-made skirts or skirt layers? So many choices of skirt layers, I'm confused. 
If I go the layer route; how many layers to make a full skirt? When I called Barlow's, the guy said it was cheaper buying pre-made. Do I want regular bands or umbrella bands?
I have heard of something called a living skirt by a name brand company and a mop jig, that's what I want to create.
On the jig head, what's the norm as far as the eye, flat or standard? Does it make a difference?
OK, I'll chime in with two cents here:
-Skirts/Bands: If you buy pre-made skirts you won't be able to get your own unique colors, but they are pre done so you will save a little time. I love putting together my own skirts with tabs and coming up with those custom colors you can't really get anywhere else. If you want your skirts to stay flared all the time, use umbrella bands (more expensive). If you want the action to pulsate all the way in and out, use flat bands. I prefer the flat bands because sometimes that profile such as on a swim jig, will mimic gill action on a bait fish. Some folks use wire to tie their skirts, but I don't like wire because it tends to cut through the band relatively quickly.
-Living Image skirts: pro: SWEET patterns. con: .56 cents PER tab. I use 3 tabs on my jigs so you can see the math there.
-Line ties: I prefer a 90 degree flat eye on a stand up jig or anything I want on the bottom with a trailer. On a swim jig if you are just chucking and winding, my opinion is it is user preference...
-where to buy: I won't even try and name all the sources, but there are MANY. Start with ebay and you will find your colors no matter what species you are after.
-Overall: are you selling these jigs or using for personal use only? That is going to be the main question regarding how you are going to want to proceed...